The Cambridge Primary Mathematics series consists of a Learner’s Book, Boost eBook, Workbook and Teacher’s Guide with Boost Subscription for each Cambridge Primary stage. Learner’s Books Boost eBook Workbook Teacher’s Guide with Boost Subscription Stage 1 (ages 5–6) 9781398300903 9781398300934 9781398301153 9781398300781 Stage 2 (ages 6–7) 9781398300941 9781398300972 9781398301177 9781398300798 Stage 3 (ages 7–8) 9781398300989 9781398301016 9781398301184 9781398300804 Stage 4 (ages 8–9) 9781398301023 9781398301054 9781398301207 9781398300811 Stage 5 (ages 9–10) 9781398301061 9781398301092 9781398301221 9781398300828 Stage 6 (ages 10–11) 9781398301108 9781398301139 9781398301245 9781398300835 * Age ranges are for guidance only To explore the entire series, visit www.hoddereducation.com/cambridgeprimary-maths The audio files are FREE to download from: www.hoddereducation.com/cambridgeextras Look at the picture on the cover. Work in pairs and answer the questions. Activity box 1 What numbers can you see? 2 How many odd numbers are there? 3 What is the biggest number you can see? 4 How many football boots can you see? 5 David scored 2 goals. Zara scored 4 more than David. How many goals did Zara score? 6 Half a match was 10 minutes long. How long was the whole game? Cambridge Primary Mathematics Second Edition Learner’s Book 2 Catherine Casey Steph King Josh Lury Series editors: Paul Broadbent Mike Askew 300941_CP_Maths_LB2_2e_TP_V1.indd 9781398300941_HCP_MATH_S2_LB.indb1 1 11/08/2020 2021/05/28 14:51 15:53 Cambridge International copyright material in this publication is reproduced under licence and remains the intellectual property of Cambridge Assessment International Education. Third-party websites and resources referred to in this publication have not been endorsed by Cambridge Assessment International Education. 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The logging and manufacturing processes are expected to conform to the environmental regulations of the country of origin. Orders: please contact Hachette UK Distribution, Hely Hutchinson Centre, Milton Road, Didcot, Oxfordshire, OX11 7HH. Telephone: +44 (0)1235 827827. Email education@hachette.co.uk Lines are open from 9 a.m. to 5 p.m., Monday to Friday. You can also order through our website: www.hoddereducation.com ISBN: 978 1 3983 0094 1 © Catherine Casey, Steph King, Josh Lury 2021 First published in 2017 This edition published in 2021 by Hodder Education, An Hachette UK Company Carmelite House 50 Victoria Embankment London EC4Y 0DZ www.hoddereducation.com Impression number 10 9 8 7 6 5 4 3 2 1 Year 2025 2024 2023 2022 2021 All rights reserved. Apart from any use permitted under UK copyright law, no part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying and recording, or held within any information storage and retrieval system, without permission in writing from the publisher or under licence from the Copyright Licensing Agency Limited. Further details of such licences (for reprographic reproduction) may be obtained from the Copyright Licensing Agency Limited, www.cla.co.uk Cover illustration by Lisa Hunt, The Bright Agency Illustrations by James Hearne, Natalie and Tamsin Hinrichsen, Val Myburgh, Vian Oelofsen Typeset in FS Albert 17/19 by IO Publishing CC Printed in Italy A catalogue record for this title is available from the British Library. 9781398300941_HCP_MATH_S2_LB.indb 2 2021/05/28 15:53 Contents How to use this book 4 Term 1 Unit 1 Numbers to 100 6 Unit 2 Addition and subtraction 13 Unit 3 Shapes, direction and movement 28 37 Unit 4 Statistical methods and chance Unit 5 Multiplication and division 43 Unit 6 Time and measurement 58 Term 1 Review66 Term 2 Unit 7 Addition and subtraction 68 Unit 8 Money 81 Unit 9 Number patterns and place value 88 Unit 10 Time and measurement 100 Unit 11 Shapes, direction and movement 112 Unit 12 Fractions 120 Term 2 Review125 Term 3 Unit 13 Statistical methods and chance 127 Unit 14 Number patterns and place value 137 Unit 15 Addition and subtraction 147 Unit 16 Multiplication and division 161 Unit 17 Fractions 178 Unit 18 Time and measurement 182 Term 3 Review194 Mathematical dictionary Thinking and Working Mathematically (TWM) skills vocabulary 9781398300941_HCP_MATH_S2_LB.indb 3 196 200 2021/05/28 15:53 How to use this book This book will help you to learn about mathematics. Explore the picture or problem. What do you see? What can you find? Understand new Maths words. The Mathematical dictionary at the back of the book can help you. Unit 11 Shapes, direction and movement Position and movement Explore Where is the parrot? Maths words turn clockwise anticlockwise whole turn half turn quarter turn This icon shows you that the activity links with other subjects in your school curriculum. Learn A turn changes the direction you are facing. Your position stays the same. 115 9781398300941_HCP_MATH_S2_LB_11.indd 115 2021/05/28 15:47 Unit 5 Multiplication and division Learn new mathematics skills with your teacher. Look at the pictures to help you. Learn There are 10 baseball bats. We can put them in groups of 2. How many groups can we make? 2 4 6 8 10 10 divided into groups of 2 is 5 groups, so: 10 ÷ 2 = 5. Can we put the 10 baseball bats in groups of 5? How many groups can we make this time? 10 ÷ 5 = Practise The shaded questions show you what you need to do. 1 You will need 20 counters. Find how many groups each time. Make groups of 5. a Make groups of 2. 20 ÷ 5 = 4 b Make groups of 10. 20 ÷ 2 = 20 ÷ = 2 There are 30 tennis rackets. Maris puts 10 in each basket. How many baskets will she use? Write the division sentence. 3 a Look at the basketballs in groups of 5. How many groups are there? b Complete the division sentence. Remember to write any answers in your notebook, not in this textbook. ÷5= Let’s talk What can David do to help him make groups of 5 or 10 for division? Try out your ideas to solve: I can count in twos and 60 ÷ 10 = 30 ÷ 5 = to help make groups of 2 for division. 54 9781398300941_HCP_MATH_S2_LB_05.indd 54 2021/05/28 15:48 4 9781398300941_HCP_MATH_S2_LB.indb 4 2021/05/28 15:53 How to use this book Do the Practise activities to learn more. Work like a mathematician. Unit 4 Statistical methods and chance Practise David asked his friends what their favourite fruit is. Fruit Number of children ll llll llll lll l Try this activities make you think carefully about mathematics. llll 1 Write the totals. 2 Use your results to draw a block graph. 3 Answer these questions about the block graph. a How many children like mangoes? b How many children like oranges? c Which is the most popular fruit? d Which is the least popular fruit? e How many more children like oranges than mangoes? f How many children did David ask? Try this Ask your friends what their favourite fruit is. Create a block graph. This star shows you the activities that require you to Think and Work Mathematically. How will you collect the data? Which categories or types of fruit will you choose? For Let’s talk activities, talk about your ideas. Let’s talk You have looked at tally charts, block graphs and pictograms. Which do you like best? Why? Use your critiquing skills. Which is most useful? When would you use each one? 39 9781398300941_HCP_MATH_S2_LB_04.indd 39 2021/05/28 15:46 Do each Quiz to find out how much you have learnt. This icon shows you that audio material is available. Listen and you will learn. Mathematical dictionary Unit 1 Numbers to 100 Quiz 1 Make these numbers on ten frames. a Seven b Twelve 2D shapes two-dimensional geometric shapes; flat shapes with sides and angles c Seventeen 2 a Write the missing numbers. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 28 29 30 31 32 33 34 35 36 37 38 39 40 43 44 45 46 47 48 49 41 51 52 53 54 55 56 57 58 61 62 63 64 65 66 67 71 72 73 74 75 76 77 78 81 82 83 84 85 86 87 88 91 92 93 94 95 96 97 98 circle triangle square rectangle pentagon hexagon 3D shapes three-dimensional geometric shapes; solid shapes with faces, edges and corners; see also face, edge and corner cube 59 60 69 70 79 80 99 100 sphere cuboid triangular prism cylinder square-based pyramid A addition a calculation of the sum of two numbers or things amount the total of things such as numbers, size or value anticlockwise in the opposite direction to the hands of a clock array an arrangement made up of rows and columns 90 b Explain how you know what the missing numbers are. 3 Estimate how many people are in your class. Count to check. 4 a Estimate how many books are on a shelf. Count to check. b Estimate how many pencils are in the class. Count to check. 12 9781398300941_HCP_MATH_S2_LB_01.indd 12 cone B block graph a diagram to show information C calculation a way of finding the number of something calendar a chart or pages that show the months and days of a whole year capacity the largest amount that something can contain Carroll diagram a table used for sorting things Multiple of 5 Not a multiple of 5 10, 20, 30 2, 6, 12 Not an even 5, 15, 25 number 3, 7, 11 Even number category a division, class or certain type of thing; music has categories such as hip hop, folk, blues, pop cent(s) a coin value centimetre (cm) there are 100 centimetres in a metre chance a possibility of something happening clockwise in the same direction as the hands of a clock coin a piece of metal used as money 196 2021/05/28 15:46 9781398300941_HCP_MATH_S2_LB_19.indd 196 2021/05/28 15:45 5 9781398300941_HCP_MATH_S2_LB.indb 5 2021/05/28 15:53 1 Numbers to 100 Reading and writing numbers to 20 Explore Look at the picture of a night sky. Can you see different groups of stars? Say how many stars are in each group. Count them to check. Are there different ways to count each group? Do you need to count one by one? Learn One ten frame is full. The other ten frame has 9 counters. Maths words count twenty estimate 19 is 10 and 9 more. Now take 18 counters. Show the different ways you can make 18 on 2 ten frames. 6 9781398300941_HCP_MATH_S2_LB.indb 6 2021/05/28 15:53 Unit 1 Numbers to 100 Practise 1 Make these numbers on ten frames. Draw each pattern you make. b 5 11 a 1 2 a Find the matching pairs. 20 twelve 12 seventeen 7 four 15 c 11 17 fourteen eleven 10 20 14 twenty seven b Which card does not match? 3 How many cubes are there? Estimate. Then count to check. Copy the table and write your answers. I estimated … a b c I counted … d Try this Draw a space picture. Show groups of stars that add up to 20. Then add some other space objects. Let’s talk Challenge a partner to estimate how many stars there are in each group in your space picture. Then count the groups of stars together aloud. 7 9781398300941_HCP_MATH_S2_LB.indb 7 2021/05/28 15:53 Unit 1 Numbers to 100 Reading and writing numbers to 100 Maths words hundred numeral thirty forty fifty Explore Look at the hundred (100) number grid. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 Which numbers do you know? Can you see any number patterns? 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 Learn Point to and say each numeral on the number track. Find the matching words. 10 20 30 ten twenty seventy 40 thirty eighty 50 60 forty ninety 70 fifty 80 90 100 sixty hundred Now practise counting from 21 to 29. 21 22 23 24 25 26 27 28 29 Twenty-one, twenty-two … How do I go on? 8 9781398300941_HCP_MATH_S2_LB.indb 8 2021/05/28 15:53 Unit 1 Numbers to 100 Practise 1 Say each number aloud. 31 32 33 34 35 36 37 38 39 40 48 49 58 59 2 Write the missing numbers in words and numerals. a 41 b 51 43 44 52 45 54 47 56 3 Which numbers are wrong? 61 62 63 65 64 66 67 68 69 70 71 27 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 98 90 91 92 93 94 95 96 97 89 99 100 Try this Let’s talk Use 2 of the cards below to make a number. How many different numbers can you make? A numeral is a figure or symbol that stands for a number. 1 3 0 7 I made thirteen. I made seventy-three. You need a large 100 grid and counters. Play with a partner. Take turns to cover 5 numbers on the 100 grid. Write the hidden numbers in words and as numerals. Score a point for each correct word or numeral. 9 9781398300941_HCP_MATH_S2_LB.indb 9 2021/05/28 15:53 Unit 1 Numbers to 100 Estimating and counting to 100 Explore David and Zara are counting to 100. Thirty-eight, thirty-nine, thirty-ten, … I am lost! Please help me. I see a pattern in the numbers. This helps me to count correctly. Estimate the number of marbles, then count to check. Learn The paperclips fell out of the box. Discuss the children’s estimates. Then count to check. I can see a lot more than 10. Is it nearly 100? Practise 1 Use a 100 grid to practise these counting patterns. a Start on 1. Count up to 50. b Start on 63. Count up to 83. c Start on 25. Count up to 45. d Start on 100. Count back to 1. 10 9781398300941_HCP_MATH_S2_LB.indb 10 2021/05/28 15:53 Unit 1 Numbers to 100 Practise (continued) 2 Estimate. Then count to check. b a c d Try this Make your own number grid. Invent a different pattern for placing the numbers. Challenge your classmates to count on your number grid. Let’s talk Work in a group. Use 100 cubes or counters. Place some of the cubes or counters in a circle. All group members must estimate how many there are. Then count together to check. 11 9781398300941_HCP_MATH_S2_LB.indb 11 2021/05/28 15:53 Unit 1 Numbers to 100 Quiz 1 Make these numbers on ten frames. a Seven b Twelve c Seventeen 2 a Write the missing numbers. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 28 29 30 31 32 33 34 35 36 37 38 39 40 43 44 45 46 47 48 49 58 59 60 69 70 79 80 41 51 52 53 54 55 56 57 61 62 63 64 65 66 67 71 72 73 74 75 76 77 78 81 82 83 84 85 86 87 88 91 92 93 94 95 96 97 98 90 99 100 b Explain how you know what the missing numbers are. 3 Estimate how many people are in your class. Count to check. 4 a Estimate how many books are on a shelf. Count to check. b Estimate how many pencils are in the class. Count to check. 12 9781398300941_HCP_MATH_S2_LB.indb 12 2021/05/28 15:53 2 Addition and subtraction The relationship between addition and subtraction Explore Let’s also buy some lemonade! Lemonade 2 friends join you in the line to buy lemonade. How many children are in the line now? When the first 3 children have paid for their lemonade, how many are left in the line? What do you notice? Learn Maths word inverse In the Explore box above: 5 + 3 = 8 and 8 – 3 = 5. +3 children 0 1 2 3 4 5 6 7 8 9 10 8 9 10 –3 children 0 1 2 3 4 5 ✗ 6 ✗ 7 ✗ When we add 3 and then subtract 3, we go back to the start. Addition and subtraction are inverse operations because one operation undoes the other. 13 9781398300941_HCP_MATH_S2_LB.indb 13 2021/05/28 15:53 Unit 2 Addition and subtraction Practise 1 Give the addition and subtraction sentences to match each pair of number lines. a 0 1 2 3 4 5 6 7 8 9 10 ✗ ✗ 0 1 2 3 4 5 6 7 8 9 10 ✗ ✗ b 0 1 2 3 4 5 6 7 8 9 10 0 1 2 3 4 5 6 7 8 9 10 + = – = – = + = 2 Copy these inverse addition and subtraction wheels. Look at the example and then complete them. Write the matching addition and subtraction sentences. a b c add add add 3 add 4 2 5 subtract 3 5 7 6 subtract subtract 4 6 9 subtract Let’s talk What could the missing numbers be in this set of related facts? + = 9 9 – = + = 9 9 – = Share your ideas with the group. Have you all picked the same numbers? Why? 14 9781398300941_HCP_MATH_S2_LB.indb 14 2021/05/28 15:53 Unit 2 Addition and subtraction Addition and subtraction facts for 10 Explore Maths words total amount complement Look at the children’s number cards! 7 6 What are the missing numbers? 2+ + 6 = 10 = 10 10 = 2 + 10 = What other totals of 10 can you make? 2 3 +6 4 0 10 1 9 5 8 Learn We can use the addition number facts for 10 to find the subtraction facts. 6 + 4 = 10 10 – 4 = 6 When we take away 4 from 10, it leaves 6. The number line shows that we subtracted the same amount that we added. 6 + 4 = 10 0 1 2 3 4 5 6 7 8 9 10 10 – 4 = 6 15 9781398300941_HCP_MATH_S2_LB.indb 15 2021/05/28 15:53 Unit 2 Addition and subtraction Practise 1 Write the addition and subtraction facts. a + = 10 b – = c + = 10 d – = 2 Look at the hands. Write an addition and subtraction fact. a b 8 + 2 = 10 7+ 10 – 2 = 8 10 – 3 = = 10 + 10 – = 10 = 3 Here are 2 number facts for the flowers. 2 + 8 = 10 and 10 – 8 = 2 Write 2 number facts for each row of flowers. a b c 16 9781398300941_HCP_MATH_S2_LB.indb 16 2021/05/28 15:53 Unit 2 Addition and subtraction Try this Let’s talk We say that two numbers that total 10 are complements of 10. How many complements of 10 can you remember? Show a friend how you answered these questions using number facts for 10. a Annay has 10 stickers and gives away 3. How many does he have left? b There are 10 cars in the car park and 8 drive away. How many are left? c Viti has 10 cents. She spends 5 cents. How many cents does she have left? Pairs that total 20 Explore Zara and Annay want to put 20 pencils in a pot. Which 2 packs of pencils can they put together to make 20? Which other pairs of pencils make 20? Can they fill 5 pots? 17 9 3 20 20 pencils 11 20 pencils 13 5 7 15 20 pencils pencils 20 pencils 6 17 9781398300941_HCP_MATH_S2_LB.indb 17 2021/05/28 15:53 Unit 2 Addition and subtraction Learn We can use what we know about complements of 10 to help us find complements of 20. Look at the examples. What do you notice? What is the same? What is different? 20 is 10 more than 10. 16 is 10 more than 6. 6 + 4 = 10 16 + 4 = 20 What number is 10 more than 4? Can you use this to make another complement of 20? Practise 1 Find the missing numbers to complete the complements of 20. b c d a 20 20 20 20 11 3 6 7 2 a Complete the number sentences. 12 + = 20 3+ = 20 + 6 = 20 2+ = 20 13 + = 20 + 16 = 20 b What patterns do you notice? Let’s talk What should you look for when finding complements of 20? Make up some rules that will help others. 18 9781398300941_HCP_MATH_S2_LB.indb 18 2021/05/28 15:53 Unit 2 Addition and subtraction Addition and subtraction with numbers to 20 Explore Maths words Zara and Jack play a game. part-part-whole model They number 20 stones from 1 to 20. regroup Zara always adds the two numbers that she turns over. Jack always subtracts the smaller number that he turns over from the larger number. Who will make a number more than 10? Who will make a number less than 15? 20 4 What numbers did the children make? 5 9 What other numbers could they make on their next turn? Play the game with a partner. Learn On her first turn, Zara adds 9 and 4. She uses a number line to help her. 0 1 2 3 4 5 6 7 8 +1 9 +3 10 11 12 13 14 15 She adds 1 and then she adds 3. Why do you think she does this? The part-part-whole model also shows Zara’s addition: Zara makes a 10. She can regroup (break up) the 4 into 1 + 3 because she knows that 9 and 1 is a complement of 10. 4 9 + 1 + 3 = 13 10 19 9781398300941_HCP_MATH_S2_LB.indb 19 2021/05/28 15:53 Unit 2 Addition and subtraction Practise Oh look, 7 + 6 is a bit more than 6 + 6. We say that 7 + 6 is a near double. Can you spot any other near doubles in the questions? 1 Complete these additions. Draw number lines or part-part-whole models to help you. a 11 + 4 = b 12 + 4 = 8+ 7 = d 9 + 10 = c 2 Complete the additions. How will you regroup the red sticks of cubes to help you make a 10? b c a + + + 3 a A bag of stones is 6 kg heavier than a 13 kg bag of sand. What is the mass of the bag of stones? b A crayon is 5 cm shorter than a pencil. The crayon is 8 cm long. How long is the pencil? Try this Which additions have totals greater than 15? Do not calculate. 8+5 13 + 1 9+8 16 + 4 5+6 3 + 13 6 + 10 Explain to a partner how you know. 20 9781398300941_HCP_MATH_S2_LB.indb 20 2021/05/28 15:53 Unit 2 Addition and subtraction Learn Jack subtracts 6 from 14. He uses a number line to help him. –2 0 1 2 3 4 5 6 7 8 9 –4 10 11 12 13 14 15 He subtracts 4. Then he subtracts 2. Why do you think he does this? Practise 1 Complete these subtractions. Draw number lines or part-part-whole models to help you. a 20 – 7 = b 15 – 6 = 19 – 7 = 15 – 7 = 18 – 7 = 14 – 6 = –7= 14 – =7 2 Annay has $17. Maris has $16. Annay spends $4 on a book and then $8 on a ball. Maris spends $12 on a game. Who has more money left? How much more? Try this Jack continues to play the 1 to 20 stones game from Explore on page 19. He says he must always regroup (break up) the smaller number to help him subtract it from the larger number. Do you agree? Can you think of other methods you could use? Give some examples. 20 5 21 9781398300941_HCP_MATH_S2_LB.indb 21 2021/05/28 15:53 Unit 2 Addition and subtraction Adding small numbers Explore Zara and David want to buy some balloons. Which balloons can the children buy? Can they buy 2 balloons each? Can they buy 3 each? How will you add the numbers to check? 5 2 9 8 4 3 I want my balloons to have a total of more than 15 but less than 20. 2 5 8 6 1 7 4 3 I want my balloons to have a total of less than 15. Learn When we add small numbers, it helps to look for pairs that total 10 first. 8+2+6= 8 and 2 total 10. Can you see a pair that totals 10 in this example? Remember that we can add in any order. 5 +4+ 5 10 10 and 6 total 16, so 8 + 2 + 6 = 16 Can you also see a double? 22 9781398300941_HCP_MATH_S2_LB.indb 22 2021/05/28 15:53 Unit 2 Addition and subtraction Practise 1 Complete these additions. Draw number lines or part-part-whole models to help you. a + + Make an estimate b + + first. Will the total c + + be greater than 10 d each time? Will it + + be less than 20? 2 Use ten frames and counters to add How do you know? these. First find a pair that totals 10. a 4+6+7= b 3+3+7= c 8+1+9= d 5+ 3 + 7 + 5 = 3 Maris has some ribbon: 7 metres of red, 8 metres of blue and 3 metres of yellow. How many metres of ribbon does she have in total? Try this Rewrite these additions to show the order you will add them. 3+4+6= 2+5+3= 1+3+9+2= 2+5+5+8= Let’s talk Sometimes you will not find a pair of numbers that total 10 straight away. What can you do to help you complete these additions? 3 + 4 + 3 7+2+1 3 + 2 + 5 6+8+6 Share your ideas with a partner. Can you make up some other examples that you might add in a similar way? 23 9781398300941_HCP_MATH_S2_LB.indb 23 2021/05/28 15:53 Unit 2 Addition and subtraction Adding multiples of 10 Explore Annay is exploring patterns. He makes rows of circles and triangles. Maths words multiple of 10 equal How many circles do I use in each pattern? How many triangles? How many shapes altogether? What other patterns can you make with the rows? Talk about the number of circles and triangles each time. Learn There are 10 shapes in each row of Annay’s patterns. We can count the rows in tens. A number that can be counted in tens is called a multiple of 10. There are 10 rows of ten in each pattern. 10 tens is equal to 100. Look at the diagrams below. They show other number facts to 10 to help you add multiples of 10. + = 4 ones + 3 ones = 7 ones + = 4 tens + 3 tens = 7 tens What is the same about these additions? What is different? 4 tens is equal to 40. 3 tens is equal to 30. 7 tens is equal to 70. So, 40 + 30 = 70. 24 9781398300941_HCP_MATH_S2_LB.indb 24 2021/05/28 15:53 Unit 2 Addition and subtraction Practise Complete the matching number sentences each time. 1 Here are some more of Annay’s patterns. a tens + tens = tens + = 100 b tens + + tens = tens = 100 c tens + + 2 a tens = = 100 ones + + So, tens + and + b ones + + tens So, tens + and + ones = tens = ones tens = ones = tens = ones tens = 25 9781398300941_HCP_MATH_S2_LB.indb 25 2021/05/28 15:53 Unit 2 Addition and subtraction Practise (continued) c ones + + So, tens + and + ones = ones tens = tens = 3 Complete these additions. a 30 + 40 = b 20 + 70 = c 50 + = 60 40 + 30 = 70 + 20 = 10 + = 60 50 + 30 = 70 + 30 = + 50 = 70 4 A farmer planted 70 seeds. 20 seeds grew into plants. How many seeds did not grow? Try this Sort these calculations into sets by their totals. 20 + 60 90 + 10 Total is 80 40 + 60 10 + 80 Total is 90 50 + 40 20 + 80 Total is 100 26 9781398300941_HCP_MATH_S2_LB.indb 26 2021/05/28 15:53 Unit 2 Addition and subtraction Quiz 1 Complete these number sentences: a 4 + 7 = 11 so – b 5 + 6 = 11 so –6= c 8 + 3 = 11 so – =4 = 2 Write the addition and subtraction facts for each of these. b c a 10 10 10 3 7 6 4 1 9 3 True or false? a 12 + 8 = 20 b 14 + 5 = 20 c 7 + 12 = 20 d 8 + 12 = 20 4 Complete these additions and subtractions. a 11 + 6 = d 6+ = 17 b 9+8= c 15 – e 20 – 8 = f 15 – 7 = = 11 5 There are 14 goats on the mountain. Five more goats arrive. How many goats are on the mountain now? 6 Complete each number sentence. a 3 + 5 = 8, so 30 + 50 = b 4 + 3 = 7, so 40 + = 70 c 5 + 5 = 10, so + = 100 d 8 + 2 = 10, so + = 100 27 9781398300941_HCP_MATH_S2_LB.indb 27 2021/05/28 15:53 3 Shapes, direction and movement 2D and 3D shapes Explore Look at the pictures that the children are holding. They show different shapes! Maths words corner curved side face edge Name the 2D shapes that you can see. Name the 3D shapes that you can see. 28 9781398300941_HCP_MATH_S2_LB.indb 28 2021/05/28 15:53 Unit 3 Shapes, direction and movement Learn This table shows the features of 2D shapes. Object Name of shape Description/features Circle 0 corners 1 curved side Triangle 3 corners 3 sides Square 4 square corners 4 sides of equal length Rectangle 4 square corners 4 sides Opposite sides of equal length Hexagon 6 corners 6 sides This table shows the features of 3D shapes. Object Name of shape Description/features Cone 1 circle face, 1 curved surface Cuboid 8 corners, 6 faces, 12 edges Sphere 1 curved surface Cylinder 2 circle faces, 1 curved surface 29 9781398300941_HCP_MATH_S2_LB.indb 29 2021/05/28 15:53 Unit 3 Shapes, direction and movement Learn (continued) Circles are all around us. A circle has a centre point. The distance from the centre to any point on the curved side is always the same. centre point The table below shows one way to sort these shapes. Shapes that have 4 corners Shapes that do not have 4 corners Practise 1 Which shapes are circles? a b c d f g h i e 30 9781398300941_HCP_MATH_S2_LB.indb 30 2021/05/28 15:53 Unit 3 Shapes, direction and movement Practise (continued) 2 Complete a table like this. Shape Number Number of corners of faces 0 Cylinder Number of edges 3 2 Cuboid Triangularbased prism Triangularbased pyramid 3 Write two special features of each shape. square a cube b d octagon e pentagon 4 corners 4 sides c square-based pyramid triangular prism 4 What 2D shapes are the faces of these 3D shapes? b a square triangle c rectangle d hexagon Some 3D shapes have different face shapes. 31 9781398300941_HCP_MATH_S2_LB.indb 31 2021/05/28 15:53 Unit 3 Shapes, direction and movement Practise (continued) 5 Sort each set of shapes into 2 groups. Explain your groups. a bicycle wheel textbook car tyre clock window button square-based pyramid sphere cube cone cuboid cylinder cardboard box ball of string box of tissues golf ball traffic cone football b c 6 This shape has This shape has straight sides. straight sides. It has 3 corners. It has 4 corners. a What is the same about the shapes? b What is different about the shapes? Try this Jack and Maris are playing draughts. How many squares can you see? Let’s talk Look at the shapes around you. How many circles can you find? Explain the features of a circle to a partner. 32 9781398300941_HCP_MATH_S2_LB.indb 32 2021/05/28 15:53 Unit 3 Shapes, direction and movement Patterns and pictures Explore Jack and Annay are decorating bags. They have printed patterns. What shape is next in Annay’s pattern? What shape is next in Jack’s pattern? How are the patterns different to each other? Learn Patterns and sequences are made from shapes or numbers repeating. Maths words pattern sequence What shape is next? What is the pattern that is repeated? What shape is next? What is the pattern that is repeated? 33 9781398300941_HCP_MATH_S2_LB.indb 33 2021/05/28 15:53 Unit 3 Shapes, direction and movement Learn The picture shows a racing car track! What 2D shapes can you see? What 3D shapes can you see? This picture shows a jungle model that Elok made! What 3D shapes can you see? What 2D shapes can you see? 34 9781398300941_HCP_MATH_S2_LB.indb 34 2021/05/28 15:54 Unit 3 Shapes, direction and movement Practise Draw the next shape in each sequence for questions 1 and 2. 1 a b c 2 a b c 3 What shapes do you see in the picture? a b e c d d b a e f c f Try this Let’s talk Use modelling clay to make 3D shapes. Can you make an animal from your shapes? What is the pattern? 35 9781398300941_HCP_MATH_S2_LB.indb 35 2021/05/28 15:54 Unit 3 Shapes, direction and movement Quiz 1 a Which 2D shapes is the robot made of? b How many sides does each shape have? c How many corners does each shape have? 2 a Write the name of each shape, A and B. b How many faces does each shape have? c How many edges does each shape have? d How many corners does each shape have? A B 3 Sort these shapes in 2 different ways. 4 Copy the pattern and draw the next shape each time. a b 36 9781398300941_HCP_MATH_S2_LB.indb 36 2021/05/28 15:54 4 Statistical methods and chance Pictograms and block graphs Explore The children are having fun at the beach! Maths words popular tally chart tally data block graph pictogram category Tally chart Fishing |||| In the sea |||| What is the most popular activity? Which activity do you like best? Look at the tally chart. Have you used one? Flying a kite ||| Reading || 37 9781398300941_HCP_MATH_S2_LB.indb 37 2021/05/28 15:54 Unit 4 Statistical methods and chance Learn Zara asked her friends what their favourite colour is. She made a tally. The picture shows you how she did this. What is your favourite colour? Blue ||| Red |||| || Orange || Green Record or keep track of each person as a line. Remember that the fifth line goes across the first four lines. |||| Zara used the information or data to draw a block graph and a pictogram. Number of children A block graph to show children’s favourite colours 10 9 8 7 6 5 4 3 2 1 0 A pictogram to show children’s favourite colours Blue Red Orange Green Blue Red Orange Favourite colours Green Key: = 1 person What is different about the block graph and the pictogram? 38 9781398300941_HCP_MATH_S2_LB.indb 38 2021/05/28 15:54 Unit 4 Statistical methods and chance Practise David asked his friends what their favourite fruit is. Fruit Number of children ll llll llll lll l llll 1 Write the totals. 2 Use your results to draw a block graph. 3 Answer these questions about the block graph. a How many children like mangoes? b How many children like oranges? c Which is the most popular fruit? dWhich is the least popular fruit? eHow many more children like oranges than mangoes? f How many children did David ask? Try this Ask your friends what their favourite fruit is. Create a block graph. How will you collect the data? Which categories or types of fruit will you choose? Let’s talk You have looked at tally charts, block graphs and pictograms. Which do you like best? Why? Use your critiquing skills. Which is most useful? When would you use each one? 39 9781398300941_HCP_MATH_S2_LB.indb 39 2021/05/28 15:54 Unit 4 Statistical methods and chance Venn diagrams and Carroll diagrams Maths words Venn diagram Carroll diagram Explore How have these shapes been sorted? What could the sorting labels be? Learn We use Venn diagrams and Carroll diagrams for sorting numbers or objects. For example, look at these numbers: 2 5 14 10 25 6 15 20 12 35 Which numbers are even numbers? Which numbers are multiples of 5? The numbers have been sorted in these diagrams. Venn diagram Carroll diagram Even numbers 2 6 12 14 Multiples of 5 10 20 5 25 35 15 Multiples of 5 Even numbers Not even numbers 10 20 5 15 25 35 Not multiples 2 6 of 5 12 14 Where would you put the number 30? Where would you put 21? What do you notice about the diagrams? 40 9781398300941_HCP_MATH_S2_LB.indb 40 2021/05/28 15:54 Unit 4 Statistical methods and chance Practise 1 Complete a Venn diagram like this. Use these numbers: Odd numbers 5 Multiples of 5 3 20 9 11 1 10 15 7 25 2 Complete a Carroll diagram like this. Use the numbers given: 3 5 12 20 17 13 2 8 10 or bigger Not 10 or bigger Even Not even Try this Use a handful of 2D shape tiles. Choose a shape and place it into a blank Venn diagram. Repeat. How many shapes can you put into the Venn diagram before your partner guesses your rule? Let’s talk Use your critiquing skills. What is different about Venn diagrams and Carroll diagrams? What is the same about them? 41 9781398300941_HCP_MATH_S2_LB.indb 41 2021/05/28 15:54 Unit 4 Statistical methods and chance Quiz 1 This tally chart shows children’s favourite animals. Animal Tally Elephant llll l llll llll lll llll lll Zebra Rhino Lion a Use the tally chart to draw a block graph. b Write the most popular animal. c Write the least popular animal. d How many children like lions the most? e How many more children like zebras than rhinos? 2 Complete a Venn diagram like this. Use these numbers: 15 or bigger Even 8 18 5 12 15 16 20 14 3 Choose 12 numbers to complete a Carroll diagram like this. 20 or bigger Not 20 or bigger Even number Not an even number 42 9781398300941_HCP_MATH_S2_LB.indb 42 2021/05/28 15:54 5 Multiplication and division Counting in twos, fives and tens Maths word total Explore The market sells fruit. I’m going to buy some strawberries! I’m going to buy some pineapples! David has 7c. Zara has 35c. How much can they buy? Learn When Annay visits the market in Explore, he buys 6 oranges. We can count in fives to help us find out how much he spends. cents 0 5 10 15 20 25 30 Annay also buys 3 passion fruits. How much does he spend in total? 43 9781398300941_HCP_MATH_S2_LB.indb 43 2021/05/28 15:54 Unit 5 Multiplication and division Learn (continued) We can carry on counting in fives from 30. cents 30 35 40 How much change will Annay get from 50 cents? 45 Annay spends 45 cents in total. Practise Look at Explore on page 43 to answer questions 1 and 3. 1 How much do the fruits cost in total? Use counting to help you. a 7 strawberries b 3 passion fruits and 4 oranges c 5 pineapples d 5 pineapples and 3 bananas e 7 strawberries and 2 more strawberries 2 Answer these. Count back to zero each time: a in fives from 25; how many fives did you count? b in tens from 90; how many tens did you count? c in twos from 16; how many twos did you count? 3 Maris has 80 cents. She buys 6 passion fruits and 4 oranges. How much money does she have left? Let’s talk David counts in twos from zero. Zara counts in fives from zero. Which of these numbers will the children say: 40 24 20 15 21 10 9? Which numbers will they not say? Can you think of other numbers they will not say? Convince your partner. 44 9781398300941_HCP_MATH_S2_LB.indb 44 2021/05/28 15:54 Unit 5 Multiplication and division Multiplication as repeated addition Explore At the animal sanctuary, the helpers pack boxes of fruit for the animals to eat, 1 box has: 1 watermelon 2 melons 3 grapefruits 4 plums 5 pineapples 6 passion fruits 7 bananas 8 kiwi fruits 9 mangoes 10 guavas How many of each fruit are needed for 2 boxes? What patterns do you notice? Learn There are 2 melons in each box. We can count in twos to find how many melons we need for more than 1 box. +2 +2 +2 +2 +2 +2 +2 +2 +2 +2 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 For 2 boxes, we need 4 melons. We can write this as a repeated addition: 2 + 2 = 4 For 3 boxes, we need 6 melons. We can write this as a repeated addition: 2 + 2 + 2 = 6 What patterns do you notice? Maths words Write a repeated addition sentence to show repeated addition the number of melons for 4 boxes. multiplication 45 9781398300941_HCP_MATH_S2_LB.indb 45 2021/05/28 15:54 Unit 5 Multiplication and division Practise 1 Each box has 2 melons. Write the repeated addition for how many in: a 6 boxes? b 7 boxes? c 9 boxes? d 10 boxes? Use the number line in Learn to help you. 2 A box has 5 pineapples in it. a Draw a number line to show the count of 5 up to 50. b Fill in a table like this. Number of boxes Repeated Total number of addition sentence pineapples 2 5 + 5 = 10 10 5 6 10 3 A box has 10 guavas in it. a Draw a number line to show the count of 10 up to 100. bComplete a table like this. Number of boxes Repeated Total number of addition sentence guavas 2 4 7 10 Try this I think: 2 + 2 + 2 + 2 + 2 + 2 + 2 = 15 Do you agree with David? Explain your thinking. I don’t need to check Viti’s addition. I know she has made a mistake. 46 9781398300941_HCP_MATH_S2_LB.indb 46 2021/05/28 15:54 Unit 5 Multiplication and division Learn 4 boxes have 20 pineapples because: 5 + 5 + 5 + 5 = 20 0 5 box 10 box 15 box 5 is the size of each group. 4 is the number of groups. 20 is the total number of pineapples. We can write this using the multiplication (×) sign as: 5 × 4 = 20 20 box We can also say that 5 multiplied by 4 is 20. Practise 1 How many pineapples? Write a repeated addition sentence and a multiplication sentence each time. b a c d 2 True or false? a 2+2+2=2×3 b 2+2+2+2=2×5 c 2+2+2+2+2+2+2=2×6 d 2+2+2+2+2+2+2+2+2=2×9 Try this Jack’s multiplication sentences show what fruit to pack in boxes. 5 × 6 = 30 2 × 8 = 16 10 × 7 = 70 5 × 9 = 45 Which digits show the group size? Which show the number of groups? Write the repeated addition sentences to match. Why do you think Jack wrote multiplication sentences? 47 9781398300941_HCP_MATH_S2_LB.indb 47 2021/05/28 15:54 Unit 5 Multiplication and division Using arrays to show multiplication Explore These stamps were designed to celebrate the Olympic Games. Maths words array equal How can you find the total number of stamps in each set? Is there a different way? What do you notice about the way the stamps are arranged? How can this help you? Learn An array has equal rows and columns. This array has 3 rows of 5. We write: 5 + 5 + 5 or 5 × 3 How many counters in total? We can also see 5 columns of 3. We can write: 3+3+3+3+3=3×5 3 × 5 = 15 and 5 × 3 = 15 3×5=5×3 48 9781398300941_HCP_MATH_S2_LB.indb 48 2021/05/28 15:54 Unit 5 Multiplication and division Practise 1 Complete the addition and multiplication sentences for each array. Look at the example. 2 + 2 + 2 2 × 3 = 6 + + × = + = × = + + a b c + + = 6 + = + = × = Think about the number of groups and the group size each time. 2 Write 2 multiplication sentences for each set of stamps. b a c 49 9781398300941_HCP_MATH_S2_LB.indb 49 2021/05/28 15:54 Unit 5 Multiplication and division Practise (continued) 3 Use counters to make arrays that match each pair of multiplication sentences. a 2 × 5 = 10 b 2 × 6 = 12 c 2 × 7 = 14 5 × 5 = 25 5 × 6 = 30 5 × 7 = 35 d Which 2 arrays come next in this pattern? Write the multiplication sentences. Try this Choose 2 numbers. 1 2 3 4 5 10 Write a multiplication calculation. Use counters to make an array. Can you use the same total number of counters to make a different array? Write the new multiplication sentence. Let’s talk This array shows 5 × 4. Talk to a partner: Do you agree or disagree with Jack? Why might Jack think he is correct? Why is Jack wrong? Can you improve Jack’s array? 50 9781398300941_HCP_MATH_S2_LB.indb 50 2021/05/28 15:54 Unit 5 Multiplication and division Division as sharing Explore Maths words share divide The owl needs to feed the 5 owlets. How many worms must the owl find so that the owlets get an equal share? Learn The owl collects 15 worms. It shares them equally between the owlets. Each owlet gets 3 worms. 15 divided equally between 5 is 3. We can write: 15 ÷ 5 = 3 We can show this as a bar model with 5 equal parts. 3 15 worms 3 3 3 The ÷ sign means divide. 3 51 9781398300941_HCP_MATH_S2_LB.indb 51 2021/05/28 15:54 Unit 5 Multiplication and division Practise 1 You will need 20 counters. a Share them equally between 2 groups. How many are in each group? 20 ÷ 2 = b Share them equally between 5 groups. How many are in each group? 20 ÷ 5 = c Share them equally between 10 groups. How many are in each group? 20 ÷ = 2 The owl collects 30 worms. The owl divides the worms equally between the 5 owlets. How many for each owlet? Write the matching division sentence. 3 Write the matching division each time. b c a 8 10 30 4 4 2 2 2 2 2 ? ? ? ? ? ? ? ? ? ? Try this Maris cuts a 50 cm length of ribbon into 5 equal pieces. How long is each piece? Write the division sentence. Maris then cuts each piece in half. Explain why the division sentence is now: 50 ÷ 10 = Let’s talk Dividing equally between 2 is the same as halving. Do you agree? Use some examples to help convince your partner. 52 9781398300941_HCP_MATH_S2_LB.indb 52 2021/05/28 15:54 Unit 5 Multiplication and division Division as grouping Explore Sort the sports balls into groups. Maths word sort group Put an equal number of balls in each basket. How many baskets will you use each time? 53 9781398300941_HCP_MATH_S2_LB.indb 53 2021/05/28 15:54 Unit 5 Multiplication and division Learn There are 10 baseball bats. We can put them in groups of 2. How many groups can we make? 2 4 6 8 10 10 divided into groups of 2 is 5 groups, so: 10 ÷ 2 = 5. Can we put the 10 baseball bats in groups of 5? How many groups can we make this time? 10 ÷ 5 = Practise 1 You will need 20 counters. Find how many groups each time. Make groups of 5. a Make groups of 2. 20 ÷ 5 = 4 b Make groups of 10. 20 ÷ 2 = 20 ÷ = 2 There are 30 tennis rackets. Maris puts 10 in each basket. How many baskets will she use? Write the division sentence. 3 a Look at the basketballs in groups of 5. How many groups are there? b Complete the division sentence. ÷5= Let’s talk What can David do to help him make groups of 5 or 10 for division? Try out your ideas to solve: I can count in twos and 60 ÷ 10 = 30 ÷ 5 = to help make groups of 2 for division. 54 9781398300941_HCP_MATH_S2_LB.indb 54 2021/05/28 15:54 Unit 5 Multiplication and division Division as repeated subtraction Explore A group of 20 children visit the fun park for a day. Here are some of the rides. Maths word repeated subtraction Teacup ride 5 people in each car House of Mirrors 10 people at a time Fun drive ride 2 people in each c ar All the children want to go on the 3 rides. How many cars will the children need for each ride? How many groups of 10 for the House of Mirrors? Learn We can count back in fives to find how many Teacup ride cars 20 children will need. –5 0 –5 5 –5 10 –5 15 20 25 30 We need 4 cars for 20 children. We can count back (subtract) 4 groups of 5 and no children will be left. We can write this as a repeated subtraction: 20 – 5 – 5 – 5 – 5 = 0 How many cars are needed for 15 children? And for 10 children? What patterns do you notice? 55 9781398300941_HCP_MATH_S2_LB.indb 55 2021/05/28 15:54 Unit 5 Multiplication and division Practise 1 Write repeated subtraction sentences each time. How many Fun drive ride cars are needed for: a 14 children b 16 children c 18 children d 22 children? 2 Write a repeated subtraction sentence to match each number line. – 10 – 10 – 10 – 10 a 0 b 10 – 10 0 c 20 – 10 10 – 10 0 – 10 20 – 10 10 30 – 10 30 – 10 20 40 – 10 40 – 10 30 – 10 50 – 10 40 60 – 10 50 – 10 60 70 3 Zara has 80 cents to spend. She spends 10 cents on each ride. How many rides is this? Write the repeated subtraction sentence. Try this The Teacup ride can take 5 people per car. The Fun drive ride can take 2 people per car. Convince a partner that 26 people cannot be on the Teacup ride, but 26 people can be on the Fun drive ride. Let’s talk I can use repeated subtraction to solve a division. Do you agree with Annay? Try his idea for 30 ÷ 10 and 18 ÷ 2. 15 ÷ 5 = 3 15 – 5 – 5 – 5 = 0 I subtracted 3 lots of 5, as there are 3 fives in 15. 56 9781398300941_HCP_MATH_S2_LB.indb 56 2021/05/28 15:54 Unit 5 Multiplication and division Quiz 1 Count on in twos from 0 to 24. How many twos? 2 Count back in tens from 50 to 0. How many tens? 3 Count on in fives from 0 to 45. How many fives? 4 Write repeated addition and multiplication sentences to match each array of cupcakes. a b 5 A baker packs bread rolls into bags. Each bag has 4 rolls in it. a How many bread rolls are in 2 bags? b How many bread rolls are in 5 bags? c How many bread rolls are in 10 bags? 6 a The baker bakes 60 biscuits. She puts 10 on each tray. How many trays does she use? 60 ÷ 10 = b The children take 2 biscuits each from one of the trays in part a. How many children can take 2 biscuits? 7 The baker bakes 30 cupcakes. She divides them equally between 5 plates. How many cupcakes are on each plate? 30 ÷ 5 = 57 9781398300941_HCP_MATH_S2_LB.indb 57 2021/05/28 15:54 6 Time and measurement Time Explore Make a paper plate clock! You need l paper plate l felt-tip pen l split pin paper fastener l sheet of coloured card l pair of scissors Method 1 Write the numbers 1 to 12 around the paper plate. Space them evenly, as on a clock face. 2 Draw and cut out an hour hand and a minute hand from the coloured card. 3 Use the split pin to attach the minute and hour hands to the paper plate. 4 Check that the hands can move easily. Choose a time and set the hands of the clock to show this time. Maths words hour hand minute hand year month week day hour minute seconds Look at the finished clock. What time does it show? 58 9781398300941_HCP_MATH_S2_LB.indb 58 2021/05/28 15:54 Unit 6 Time and measurement Learn 1 year = 365 days 1 year = 12 months 1 week = 7 days 1 day = 24 hours 55 minute hand 0 1 hour = 60 minutes 1 minute = 60 seconds 5 50 10 45 15 40 20 35 30 hour hand 25 What time is it? How do you use the numbers on a clock? The time on an analogue clock The time on a digital clock The hour hand is pointing to the 4. The minute hand is pointing to the 12. It is 4 o’clock. It is 4 o’clock. The hour hand is pointing past the 4. The minute hand is pointing at the 2. It is 10 minutes past 4. It is 10 minutes past 4. The hour hand is pointing between the 4 and 5. The minute hand is pointing to the 8. It is 4:40 or 40 minutes past 4. It is 4:40 or 40 minutes past 4. hour minutes 59 9781398300941_HCP_MATH_S2_LB.indb 59 2021/05/28 15:54 Unit 6 Time and measurement Practise 1 Match the time on each analogue clock to the digital clock. a 1 b 2 c 3 d 4 e 5 f 6 g 7 60 9781398300941_HCP_MATH_S2_LB.indb 60 2021/05/28 15:54 Unit 6 Time and measurement Practise (continued) 2 Which is longer? a 1 day or 1 hour c 1 minute or 1 second e 1 month or 1 year g 1 day or 1 week b 1 hour or 1 week d 1 second or 1 year f 1 year or 1 week Try this Time yourself. How long does it take you to write the numbers 1 to 20? Compare your time with others in your group. How could you show your results? Let’s talk Work with a partner. Answer the questions. 1 The aeroplane took off at 3 o’clock. It landed at 8 o’clock. How long was the flight? 2 The film started at 4 o’clock. It finished 2 hours later. What time did it finish? Can you write a time question for your partner? 61 9781398300941_HCP_MATH_S2_LB.indb 61 2021/05/28 15:54 Unit 6 Time and measurement Length Explore Learn Jack and Annay are having a jumping challenge. Using non-standard units How many counters fit along the pencil? I think I can jump about 60 metres (m). Using centimetres and a ruler cm 0 cm 10 20 30 40 50 60 70 80 I think I can jump about 60 centimetres (cm). cm 10 20 30 40 50 60 70 5 10 15 The tip of the pencil is in line with the 12. The pencil is 12 cm in length. Non-standard units are all different. 80 Who made a good estimate? How far did each child jump? Who jumped the furthest? Maths words metre (m) centimetre (cm) length 62 9781398300941_HCP_MATH_S2_LB.indb 62 2021/05/28 15:54 Unit 6 Time and measurement Practise 1 How long is each item? a Estimate in counters. Then use counters to measure. b Estimate in centimetres. Then measure each item. book hand span shoe 2 How high can you jump? Estimate and then measure. Learn B Compare the sunflowers. Put the sunflowers in order from shortest to tallest. The shortest sunflower is 28 cm . A C The next is 42 cm . The tallest sunflower is 63 cm . 42 42 cm 63 63 cm 28 28cm cm 1 metre (m) = 100 centimetres (cm) The 3 sunflowers are all shorter than 1 metre. Point to something that is shorter than 1 metre. B A C Point to something that is taller than 1 metre. You can also put the sunflowers in order from tallest to shortest. shortest 28 cm 28 tallest 42cm cm 42 63cm cm 63 63 9781398300941_HCP_MATH_S2_LB.indb 63 2021/05/28 15:54 Unit 6 Time and measurement Practise 1 Estimate which items are taller or longer than 1 metre. 2 Put each set of lengths in order from shortest to longest. Use a ruler and metre stick to compare them. b 1 m, 10 m, 5 m a 4 cm, 8 cm, 6 cm d 10 m, 20 m, 15 m c 18 cm, 16 cm, 14 cm f 20 m, 30 m, 25 m e 24 cm, 28 cm, 26 cm h 35 m, 40 m, 33 m g 34 cm, 38 cm, 36 cm 3 a Estimate how many metres each item is: l the length of the classroom l the height of the door. b Measure each item in metres. Try this Measure and order different lengths of string. You need a ruler, some string and a pair of scissors. Measure and cut pieces of string in these lengths: l 5 cm l 10 cm l 15 cm l 20 cm l 25 cm. Then put your measured lengths in order from shortest to longest. Let’s talk How many items can you find in the classroom that are: l taller or longer than 1 metre? l shorter than 1 metre? How could you record this? 64 9781398300941_HCP_MATH_S2_LB.indb 64 2021/05/28 15:54 Unit 6 Time and measurement Quiz 1 Match the time on each analogue clock to the digital clock. a 1 b 2 c 3 2 Put each set of lengths in order from shortest to longest. a 3 cm, 9 cm, 12 cm, 6 cm b 13 m, 19 m, 22 m, 16 m c 23 cm, 29 cm, 32 cm, 26 cm 3 Find 3 pencils of different lengths. Use a ruler to measure each pencil in centimetres. cm 0 5 10 15 65 9781398300941_HCP_MATH_S2_LB.indb 65 2021/05/28 15:54 Term Review 1 Units 1–6 1 Take a large handful of counters. Place them in a pile. Estimate how many there are. Then count to check. Write the number as tens and ones. 2 Write the related subtraction facts. a 7 + 3 = 10 à 10 – = b 8 + 2 = 10 à 10 – = c 4 + 6 = 10 à 10 – = d 9 + 1 = 10 à 10 – = 3 Do these calculations. a 19 – 4 = c 13 + b 14 + 6 = d 18 – 5 = = 17 4 What are the next 2 shapes in each sequence? a b c 5 Sort the shapes into a table like this. 3 or more corners a b Not 3 or more corners c d e f 66 9781398300941_HCP_MATH_S2_LB.indb 66 2021/05/28 15:54 Term 1 Review 6 Complete a Venn diagram like this. Use these numbers: Odd numbers 30 or more 5 10 12 35 50 38 17 7 Write the multiplication to match each array. a b c 8 Jack has 15 marbles. He gives 5 marbles to each of his friends. How many friends will get 5 marbles? 9 Match the units of time. 1 year 7 days 1 week 24 hours 1 day 60 minutes 1 hour 12 months 10 Give the digital time for the clock. 67 9781398300941_HCP_MATH_S2_LB.indb 67 2021/05/28 15:54 7 Addition and subtraction Addition and subtraction facts for 20 Explore I will put some more shells in my bucket so that I have 20 altogether. Maths words complement inverse How many shells could David have to start with? How many more did he collect? David then puts the same number of shells back on the beach. How many does he have left in his bucket? Learn We can use complements of 20 to help us think about the number of shells David has to start with and how many more he collects. + = 20 The number line below shows a possible solution. 15 shells add 5 shells is 20 shells. 15 + 5 = 20 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 20 – 5 = 15 We can also see that 20 shells take away 5 shells leaves 15 shells. Subtraction ‘undoes’ addition so we can use our addition facts to find out subtraction facts. We say that addition and subtraction are inverses. 68 9781398300941_HCP_MATH_S2_LB.indb 68 2021/05/28 15:54 Unit 7 Addition and subtraction Practise 1 Write the addition and subtraction fact to match. a b + = + 14 15 16 17 18 19 20 – = 13 14 15 16 17 18 19 20 = – = 2 a Complete these bar models to show complements of 20. 20 20 20 ? ? ? 10 11 8 b Write matching addition and subtraction sentences for each. 3 Complete these. a 16 + = 20 20 – 4 = b 15 + c = 20 + 6 = 20 – 5 = 15 20 – 6 = Try this Write 5 pairs of items that will balance the scales. 17 g 1g 3g 20 g 10 g 2g 10 g 19 g 16 g 18 g 4g Write addition sentences and the matching subtractions. 69 9781398300941_HCP_MATH_S2_LB.indb 69 2021/05/28 15:55 Unit 7 Addition and subtraction Adding and subtracting multiples of 10 Explore The children are playing with blocks of tens. Maris adds 2 extra blocks to her pile. What is the value of her pile now? Annay uses a ball to knock blocks off his pile. What could the value of his pile be now? Maths word multiples of 10 Learn We can use addition facts to 10 to help us add multiples of 10. The total is 10 times as big. + = 1 + 9 = 10 + 10 + 90 = 100 = 10 – 9 = 1 100 – 90 = 10 Subtraction is the inverse of addition, so we can write: 1 + 9 = 10 10 – 9 = 1 10 + 90 = 100 100 – 90 = 10 70 9781398300941_HCP_MATH_S2_LB.indb 70 2021/05/28 15:55 Unit 7 Addition and subtraction Practise 1 Answer these additions and subtractions. a 80 + 20 = b 100 – 20 = c 80 + 10 = 70 + 30 = 100 – 30 = 90 – 10 = 60 + 40 = 100 – 40 = 90 – 80 = 2 Work out the related facts for each number sentence. a 40 + 60 = 100 = 100 60 + 100 – 60 = 100 – b 30 + 70 = 100 + 30 = 100 = 30 100 – = – 30 = 70 100 – = 100 – = 60 c 20 + 80 = 100 + = 100 Try this Jack starts on 40 and adds a multiple of 10. Viti starts on a number and subtracts a multiple of 10. My new number is the same as your starting number! That’s strange. How many ways can you make this true? Let’s talk 10 20 30 40 50 60 70 80 90 100 Use counters on the track to convince a friend each time. a 30 + 70 = 100 and 100 – 70 = 30 b 60 + 20 = 80 and 80 – 20 = 60 What other addition and subtraction facts can you make? 71 9781398300941_HCP_MATH_S2_LB.indb 71 2021/05/28 15:55 Unit 7 Addition and subtraction Making estimates Explore Maris and David are making buns. I need to make 4 buns for Grandpa and 5 buns for Auntie. Is there enough space in my tin? Maths word estimate I need to make 3 buns for Gran and 8 buns for Uncle. Is there enough space in my tin? What do you think? How can Maris and David check? Can they use estimates to help them? Talk about it. 72 9781398300941_HCP_MATH_S2_LB.indb 72 2021/05/28 15:55 Unit 7 Addition and subtraction Learn Maris knows that double 5 is 10. David knows that 3 and 7 are a pair that total 10. How does that help her? How does that help him? 4 is less than 5, so 4 + 5 must be less than double 5 (or 5 + 5). 8 is more than 7, so 3 + 8 must be more than 3 + 7. Practise 1 Will the answers to these additions be more or less than 10? Write the number fact you use to help you. a 6+3 b 6+5 c 8+4 d 2+7 e 5+5+1 2 Write less or more to complete these sentences. than 10. a Double 5 is 10, so 5 + 6 is than 8. b Double 4 is 8, so 4 + 3 is than 12. c Double 6 is 12, so 6 + 6 + 1 is than 20. d Double 10 is 20, so 9 + 8 is 3 Will the answers to these subtractions be more or less than 10? Write the number fact you use to help you. a 9–3 b 18 – 10 c 18 – 7 d 12 – 4 e 20 – 11 Try this Look at: 20 – 5 = 15. Will 20 – 8 be less or more than 15? Will 20 – 4 be less or more than 15? Explain how you know. Let’s talk I know that 10 + 5 = 15, so 9 + 6 must be more than 15. What do you think about Viti’s estimate? How can you improve it? 73 9781398300941_HCP_MATH_S2_LB.indb 73 2021/05/28 15:55 Unit 7 Addition and subtraction Adding small numbers Explore Play a game. Throw 3 bean bags into 3 numbered buckets. What different total scores could you get? How can you show that you have found all the different total scores? Maths word double Learn You can add numbers in any order: 3 + 2 = 2 + 3 When adding sets of numbers, look for complements of 10 or doubles. For example: 3 + 4 + 3 + 6 = First think about an estimate. double 3 = 6 3 + 4 + 3 + 6 = 16 4 + 6 = 10 Practise 1 Copy the numbers and add them. Write the answers. a 3+2+8+3= b 4+3+7+4= 4+2+8+4= 5+3+7+5= 5+2+8+5= 6+3+7+6= 6+2+8+6= 7+3+7+7= 74 9781398300941_HCP_MATH_S2_LB.indb 74 2021/05/28 15:55 Unit 7 Addition and subtraction Practise (continued) 2 The children are playing a game. They try to knock over as many skittles as they can. Who has the highest score? Name David Viti Jack Maris Throw 1st 2nd 4 2 6 6 3 3 2 8 3rd 6 3 1 4 4th 2 7 9 4 Total score 3Zara is playing a game. She throws 3 balls at the target. What can her total score be? Try to make an estimate first. Will the score be more than 15? Write some possible numbers of throws. Try this Let’s talk 3 7 2 2 Jack catches 3 fish with these numbers: 5 6 8 10 4 1 What is his total? Viti also catches 3 fish. 9 Two of her numbers are 1 and 8 . a What can the number on Viti’s third fish be? b Write all the possible totals that Viti can make. I know that we can add numbers in any order. I don’t think we can subtract numbers in any order. How can you convince Maris that she is correct? 75 9781398300941_HCP_MATH_S2_LB.indb 75 2021/05/28 15:55 Unit 7 Addition and subtraction Adding two-digit and one-digit numbers Explore The children spin a 1 to 6 spinner. Annay moves his counter on 3 spaces. What number is his counter on now? Zara spins the spinner and moves on this number of spaces. What number can her counter be on now? Learn 32 + 4 = 36 Remember that you can do addition in any order. You can count on from the larger number on a number line. Count on 4. 30 31 32 33 34 35 36 37 38 39 40 You can also use addition facts to help you. 2 + 4 = 6, so 32 + 4 = 36 Maths word addition = + 32 4 36 76 9781398300941_HCP_MATH_S2_LB.indb 76 2021/05/28 15:55 Unit 7 Addition and subtraction Practise 1 Copy the calculations. Write the answers. a 22 + 3 = b 33 + 2 = c 40 + 5 = 23 + 3 = 33 + 4 = 41 + 5 = 24 + 3 = 33 + 6 = 42 + 6 = 34 + 3 = 43 + 6 = 42 + 7 = 2 Write the number sentence and the answer. a b 24 25 26 27 28 3 Write the number sentence and the answer. a 29 23 24 25 26 27 28 29 b + + Try this Annay writes a number. He adds 5. His new number is 29. What number did he write? Make up your own problem like this. Let’s talk Jack says that 23 + 6 = 29 How many other additions can you make to give the answer 29? Use a two-digit number and a one-digit + = 29 number each time. 77 9781398300941_HCP_MATH_S2_LB.indb 77 2021/05/28 15:55 Unit 7 Addition and subtraction Subtracting a one-digit number from a two-digit number Maths word subtraction Explore What can you see in the picture? How many cars are in the car park? How many cars can drive away so there are more than 20 cars left? Give as many answers as you can. Learn 27 – 3 = 24 Always do subtraction in the order it appears. You can count back from the first number on a number line. Count back 3. 20 21 22 23 24 You can also use subtraction facts to help you. 7 – 3 = 4, so 27 – 3 = 24 25 26 27 28 29 30 27 – 3 = 24 78 9781398300941_HCP_MATH_S2_LB.indb 78 2021/05/28 15:55 Unit 7 Addition and subtraction Practise 1 Copy the calculations. Write the answers. a 29 – 4 = b 38 – 7 = c 49 – 5 = 28 – 4 = 38 – 6 = 47 – 5 = 27 – 4 = 38 – 5 = 48 – 6 = 37 – 4 = 38 – 4 = 48 – 8 = 2 Write the number sentence and the answer. a 31 32 33 34 35 36 37 38 41 42 43 44 45 46 47 48 b 3 Write the number sentence and the answer. a b Try this Viti writes a number. She subtracts a number less than 10. What number could she have written? My answer is 22! Let’s talk Talk about any patterns you notice. How can you use the patterns to find the answer to 48 – 5? Can you continue the pattern? 18 – 5 = 13 28 – 5 = 23 38 – 5 = 33 79 9781398300941_HCP_MATH_S2_LB.indb 79 2021/05/28 15:55 Unit 7 Addition and subtraction Quiz 1 Complete these calculations. a 10 + 10 = b 12 + c à 20 – 10 = = 20 à 20 – 8 = + 5 = 20 à 20 – 5 = d 17 + = 20 à 20 – = 17 2 Use 4 of these numbers once to make each number sentence correct. 80 40 10 50 a 60 – 50 = c 90 – = 50 30 b 20 + = 100 d 50 + = 80 3 100 passengers board an aeroplane. 30 are carrying a suitcase. How many passengers are not carrying a suitcase? 4 Complete these additions and subtractions. b 31 + 6 = a 39 – 4 = c 42 + = 45 d 49 – = 47 5 There are 45 pens in a box. Zara takes 4. How many are left? 6 A T-shirt costs $22. A game costs $6 more. How much is the game? 80 9781398300941_HCP_MATH_S2_LB.indb 80 2021/05/28 15:55 8 Money Understanding coins and notes Explore Maths words coin note cent dollar I have been saving up for … What coins and notes can you see? Which is worth more: 1 cent or 1 dollar? Do you ever save or spend money? What would you like to save for? Why do some people give money away? 81 9781398300941_HCP_MATH_S2_LB.indb 81 2021/05/28 15:55 Unit 8 Money Learn We can use addition facts to 10 to help add multiples of 10. The total is 10 times as big. I wonder how many 1c coins this is worth? Practise 1 Sort these coins in order from least value to greatest value. 2 Which has the least value? Try this Let’s talk I am thinking of a coin or note. It is worth more than 10 cents, but less than $10. What could it be? Has one of these machines broken? Discuss with a partner. Find all the possible answers. COIN CHANGER COIN CHANGER 82 9781398300941_HCP_MATH_S2_LB.indb 82 2021/05/28 15:55 Unit 8 Money Working out the total amount Explore Maths words total amount The children are at the market! What questions could you ask these children at the market? Learn Annay has these coins. That is 11c in total. 0 1 2 3 4 5 6 7 8 9 10 11 12 Jack has these coins. How much is the total amount? 83 9781398300941_HCP_MATH_S2_LB.indb 83 2021/05/28 15:55 Unit 8 Money Practise 1 Work out the total for each bar model. b a d c e 2 Work out the total amounts of money. a b c d 3 Work out how much money is in each bowl. Sort the total amounts in order. b c d a 4 Work out the mystery coins. a 50 cents b ? e 75 cents ? Try this Use coins or toy coins. Choose 5 coins at random. Challenge your partner to work out the total amount. Then try it with 6 coins at a time. 84 9781398300941_HCP_MATH_S2_LB.indb 84 2021/05/28 15:55 Unit 8 Money Making amounts Explore Annay and Maris are shopping. They have notes to spend! What would you buy? What notes would you have to use? What could the children buy? Learn Which coins could make exactly 35c? What notes could you use to buy the bear? 35c $14 85 9781398300941_HCP_MATH_S2_LB.indb 85 2021/05/28 15:55 Unit 8 Money Practise 1 Draw coins or notes to make each of these amounts. a 11c b 19c c 21c d$16 26c e 50c f $30 g $21 h $49 $18 $16 $1 2 Choose 2 items to buy. 4 $16 $1 $16 4 $1 $18 $18 $18 $15 $16 $17 $15 $1 4 $15 $18 4 $1$15 7 $ 17 would use. a Work out the total cost. Show the notes you Choose 3 items to buy. Work out the notes you would b use to make $1the exact amount. $15 $17 7 Price list: pen 20c pencil 15c ruler 25c eraser 10c notepad 30c 3 Zara buys 3 items from the price list. She pays using these coins. Which 3 items did Zara buy? Try this Let’s talk Zara invents her own money for a game. She only uses 2c, 5c and 30c coins. What different amounts can she make? Are there any amounts that she cannot make? Set up your own shop with price labels. Role-play shopping for the different items. Make your own coins and notes of different values. 86 9781398300941_HCP_MATH_S2_LB.indb 86 2021/05/28 15:55 Unit 8 Money Quiz 1 Look at this selection of coins and notes. a Sort them from smallest to largest value. b Sort the money from largest to smallest. 2 How much money is there each time? a b 3 Draw 2 different ways to make 26c from these coins. 87 9781398300941_HCP_MATH_S2_LB.indb 87 2021/05/28 15:55 Number patterns and place value 9 Tens and ones Explore How many tens can you see? Maths words tens ones 88 9781398300941_HCP_MATH_S2_LB.indb 88 2021/05/28 15:55 Unit 9 Number patterns and place value Learn 16 is 1 full ten and 6 ones. The 1 stands for 1 ten. The 6 stands for 6 ones. 26 is 2 full tens and 6 ones. What do the 3 and the 6 stand for in 36? How would you write a number with 6 full tens and 2 ones? I can use rods and cubes to show tens and ones. Practise 1 Write these numbers as tens and ones. a b c d 89 9781398300941_HCP_MATH_S2_LB.indb 89 2021/05/28 15:55 Unit 9 Number patterns and place value Practise (continued) 2 Write these numbers as tens and ones. a b c 3 Write these as numbers. a 2 tens and 3 ones c 9 tens and 1 one d b 4 tens and 9 ones d 8 tens and 0 ones 4 Represent (show) the number 32 in as many ways as you can. Use equipment, drawings, numbers and words. Try this Let’s talk Write the different numbers that David and Maris might have. Write each number as tens and ones. ten My number has 6 tens. My number has 6 ones. twenty thirty forty fifty sixty seventy eighty ninety What does the 0 stand for in each number? 90 9781398300941_HCP_MATH_S2_LB.indb 90 2021/05/28 15:55 Unit 9 Number patterns and place value Counting in tens and ones Explore Let’s look for tens! Thirty Ten Twenty 10 20 Fifty Sixty Forty 30 50 40 One hundred Eighty Seventy 60 70 Ninety 80 90 100 First count aloud in tens! Then use counting equipment to make each number. 91 9781398300941_HCP_MATH_S2_LB.indb 91 2021/05/28 15:55 Unit 9 Number patterns and place value Learn Look at this counting pattern. How would it continue? 3 13 23 33 I wonder why 10 more is always underneath? Practise counting on and back in tens in this pattern. Make the numbers using counting equipment. Practise 1 Make each pattern and write the next numbers. a 4, 14, 24, 34, b , , , , , 6, 16, 26, 36, , , , , , 92 9781398300941_HCP_MATH_S2_LB.indb 92 2021/05/28 15:55 Unit 9 Number patterns and place value Practise (continued) 2 Use a 100 grid. Then answer the questions below. a Choose any starting number in the top row. Count on in tens. Write the counting pattern you used. b Choose any number in the bottom row. Count back in tens. Write the counting pattern you used. 3 Copy each number track and fill in the missing numbers. a 7 b 31 61 c 88 58 d 100 17 37 67 81 28 60 10 3535 Try this Some of this number is hidden. Write all the numbers it could be. There There areare 3 tens 3 tens and and 5 ones. 5 ones. Let’s talk What would you say to explain how to count on and back in 1s from any number? I can count back from 25, but what do I do when I reach 21? 21 22 23 24 25 26 27 28 29 30 I can count on in ones from 25, but what do I do after 30? 93 9781398300941_HCP_MATH_S2_LB.indb 93 2021/05/28 15:55 Unit 9 Number patterns and place value Counting in fives Explore Let’s count in fives! Maths word fives How many fingers in each row? How many fingers in total? Estimate. Then count to check. 94 9781398300941_HCP_MATH_S2_LB.indb 94 2021/05/28 15:55 Unit 9 Number patterns and place value Learn The number track shows the counting pattern in fives. 5 1 11 21 31 41 51 61 71 81 91 10 2 12 22 32 42 52 62 72 82 92 3 13 23 33 43 53 63 73 83 93 15 20 4 14 24 34 44 54 64 74 84 94 5 15 25 35 45 55 65 75 85 95 6 16 26 36 46 56 66 76 86 96 25 30 7 17 27 37 47 57 67 77 87 97 8 18 28 38 48 58 68 78 88 98 35 40 45 50 9 10 19 20 Use your skills of 29 30 conjecturing and 39 40 characterising. 49 50 59 60 69 70 79 80 89 90 99 100 Find the fives counting pattern on the 100 grid. What do you notice? Now start on 1. Count in fives. Look at the pattern on the 100 grid. Practise 1 Count forwards and backwards in fives. Point to each number as you count. 5 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100 95 9781398300941_HCP_MATH_S2_LB.indb 95 2021/05/28 15:55 Unit 9 Number patterns and place value Practise (continued) 2 Continue these counting patterns. a 2, 7, 12, 17, , , , , , , , b 3, 8, 13, , , , , , , , , c 4, 9, 14, , , , , , , , , 3 Zara starts on 99. She counts down in fives. Which of these numbers will she say? 98 50 44 95 89 59 34 84 75 4 5 10 19 Try this A bee has 5 eyes. Count how many bees you see. How many eyes do all the bees you counted have? A group of bees fly away. When you count the eyes of those left in the hive, there are fewer than 20. How many bees could there be in the hive? Let’s talk Spread out a large number of counters or cubes. Sort them into piles of 5 to make counting them easier. Try this with different numbers of objects. 96 9781398300941_HCP_MATH_S2_LB.indb 96 2021/05/28 15:55 Unit 9 Number patterns and place value Counting in twos Explore Discuss different ways to count the penguins. How can you make sure that you are correct? Maths words twos even odd Learn Count the pile of counters in twos. How many in total? We can sort the counters into pairs. Count them in twos. How many in total? 97 9781398300941_HCP_MATH_S2_LB.indb 97 2021/05/28 15:55 Unit 9 Number patterns and place value Learn (continued) The numbers in the circles are even numbers. What do we call the numbers in between the even numbers? We call them odd numbers. Practise 1 aCount forward in twos on these rows of a 100 grid. What patterns do you notice? bCount back in twos from 40. Can you predict the numbers you will say? What if you count back from 39? 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 2 a Write all the even numbers between 30 and 50. b Write all the odd numbers between 30 and 50. 3 Take 24 counters. Share them into 2 equal groups. Now try to share 27 counters into 2 equal groups. What do you notice? Try this Predict which numbers can be shared equally between 2 groups. Then predict which numbers leave 1 left over. Can you explain what you find out? 31 32 33 34 35 36 37 98 9781398300941_HCP_MATH_S2_LB.indb 98 2021/05/28 15:55 Unit 9 Number patterns and place value Quiz Use this picture to help you answer the questions below. 1 Choose 2 players. Write each number as tens and ones in tables like this. a 10s 1s b 10s 1s 2 Estimate how many players are on the field. 3 Count the players in ones. 4 a Draw 25 footballs. b Count them in fives. 5 Count the players’ kit bags in twos. 6 Write 3 even and 3 odd numbers that you see in the picture. 99 9781398300941_HCP_MATH_S2_LB.indb 99 2021/05/28 15:55 10 Time and measurement Time Explore Maths words hour minute seconds Look at all these clocks! 01:05 03:35 Can you read the time on each clock? What different types of clocks can you see? 100 9781398300941_HCP_MATH_S2_LB.indb 100 2021/05/28 15:55 Unit 10 Time and measurement Learn 55 0 50 5 minute hand 10 hour hand 45 15 40 20 25 35 30 What time is it? What are the numbers on the outside of the clock? The time on an analogue clock The time on a digital clock The hour hand is pointing to the 10. The minute hand is pointing to the 4. It is 20 past 10. It is 20 past 10. The hour hand is pointing past the 4. The minute hand is pointing at the 3. It is 15 minutes past 4. It is four fifteen. The hour hand is pointing between the 4 and 5 The minute hand is pointing to the 8. It is four forty. It is 4:40 or 40 minutes past 4. hour minutes 101 9781398300941_HCP_MATH_S2_LB.indb 101 2021/05/28 15:55 Unit 10 Time and measurement Practise 1 Match the time on each analogue clock to the digital clock. 1 2 3 4 a b c 5 6 d e f 7 g h 8 2 Write each time as it would be on digital clocks like this. b a twenty past four c quarter past six d three o’clock Try this How many seconds can you go without blinking? Work with a partner to time each other. half-past eight Let’s talk Is there a clock in the classroom? What time is it now? What time do you have lunch? What time do you finish school? What is your favourite time of the day? Explain why. 102 9781398300941_HCP_MATH_S2_LB.indb 102 2021/05/28 15:55 Unit 10 Time and measurement Length Explore Maths words centimetres metres difference Which items would you measure in centimetres? Which items would you measure in metres? Which measuring tools are best for each measuring task? 103 9781398300941_HCP_MATH_S2_LB.indb 103 2021/05/28 15:55 Unit 10 Time and measurement Learn We can use a ruler to measure an item in centimetres. The carrot is 12 cm. Use a ruler to draw the line. How to draw a line that is 8 cm long 1 Put the ruler flat on the paper and hold it still. 2 Put your pencil on 0 cm and make a dot. 3 Put your pencil on 8 cm and make a dot. 4 Join the 2 dots, drawing along the ruler. We can add lengths together. 0 1 2 30 1 2 3 4 5 0 1 2 3 4 5 6 7 8 3 cm + 5 cm = 8 cm We can find the difference between 2 lengths. 0 0 1 1 2 2 3 3 4 4 5 6 6 cm – 4 cm = 2 cm The difference is 2 cm. 104 9781398300941_HCP_MATH_S2_LB.indb 104 2021/05/28 15:55 Unit 10 Time and measurement Practise 1 How long is the brinjal, the sweet potato and the carrot in centimetres? b a c 2 How tall is each flower in centimetres? a b c 3 Draw a line for each length. a 3 cm b 6 cm e 10 cm d 12 cm c 9 cm f 7 cm 4 Complete these additions. a 7 cm + 3 cm = b 5 cm + 9 cm = c 14 cm + 2 cm = d 18 cm + 4 cm = e 5 cm + 7 cm = f 9 cm + 3 cm = 105 9781398300941_HCP_MATH_S2_LB.indb 105 2021/05/28 15:55 Unit 10 Time and measurement Practise (continued) 5 Find the difference between each pair of straws. a 8 cm – 2 cm = cm b 7 cm – 3 cm = cm c 3 cm – 1 cm = cm Try this In April the flower was 12 cm tall. In May the flower was 20 cm tall. How much had the plant grown? Viti is 133 cm tall. Zara is 125 cm tall. How much taller is Viti than Zara? Let’s talk How many items can you find in the classroom that are: l taller or longer than 10 centimetres l shorter than 10 centimetres? How could you record this? 106 9781398300941_HCP_MATH_S2_LB.indb 106 2021/05/28 15:56 Unit 10 Time and measurement Mass Maths words mass gram (g) kilogram (kg) heaviest lightest Explore Nuts for sale! Viti has __ 12 a kilogram. Viti has 500 g. Viti has 5 kg. Who is correct? Explain why. How much will Viti’s nuts cost? 107 9781398300941_HCP_MATH_S2_LB.indb 107 2021/05/28 15:56 Unit 10 Time and measurement Learn We measure the mass of an object in grams (g) and in kilograms (kg). We can use a scale to measure how heavy an object is. Look at the scale on the right. What is the mass of the parcel? The red arrow points to 80 g. The parcel weighs 80 g. 90 0 80 10 20 70 grams 30 60 50 40 We can use signs to compare mass: < is less than > is greater than 50 g > 2 g 100 g > 10 g 4 g < 25 g 3 g < 60 g 108 9781398300941_HCP_MATH_S2_LB.indb 108 2021/05/28 15:56 Unit 10 Time and measurement Practise 1 Write the mass of each parcel. b a 90 80 0 90 10 20 80 70 grams 30 60 40 50 0 10 20 70 grams 30 60 40 50 2 Use weighing scales to find the mass of 5 objects. Record your results in a table like this. Remember to estimate the mass first. Object I estimated … Mass 100 g 90 g 175 150 125 0 g 25 100 50 75 glue 3 Annay has weighed these objects. 10 g 200 g 300 g 75 g 50 g a Which object has the heaviest mass? b Which object has the lightest mass? c Write the objects in order from lightest to heaviest. 109 9781398300941_HCP_MATH_S2_LB.indb 109 2021/05/28 15:56 Unit 10 Time and measurement Practise (continued) 4 Copy these statements. Complete them by filling in either < or >. a 10 g 11 g b 20 g 25 g c 90 g 90 kg d 20 kg 20 g e 10 kg 9 kg f 20 g 15 kg 5 Use the <, > or = signs to write a statement for each pair. b a 50 kg 100 kg 50 kg 50 kg c Try this 50 kg 40 kg Let’s talk Would you measure these in grams or kilograms: l feather l pencil l Zara l large sack of potatoes? Think of 5 other items that you would weigh in: l grams l kilograms. The children picked and then weighed tomatoes. Viti’s tomato weighed 65 g. Zara’s tomato weighed 10 g less than Viti’s. Jack’s tomato weighed 20 g more than Zara’s. How much did Jack’s tomato weigh? 110 9781398300941_HCP_MATH_S2_LB.indb 110 2021/05/28 15:56 Unit 10 Time and measurement Quiz 1 Match each analogue clock to the digital clock. 2 Use a ruler to measure the length of each pencil. b a c 3 Write the mass of the parcel. 90 80 0 10 20 70 grams 30 60 40 50 4 Put the objects in order from lightest to heaviest. a c b 10 g 350 g d e 240 g 75 g 500 g 111 9781398300941_HCP_MATH_S2_LB.indb 111 2021/05/28 15:56 11 Shapes, direction and movement Symmetry Explore Maths words line of symmetry symmetrical What a beautiful butterfly! What shapes can you see? Learn Lines of symmetry are all around us. Symmetrical means that something is the same on two or more sides. A line of symmetry shows that the shape or picture is symmetrical. It is the same on both sides when you fold it in half down the line of symmetry. line of symmetry line of symmetry line of symmetry 112 9781398300941_HCP_MATH_S2_LB.indb 112 2021/05/28 15:56 Unit 11 Shapes, direction and movement Practise 1 Copy each shape. Then draw a line of symmetry. b c d a 2 Copy the table. Draw 4 shapes under each heading. Shapes with lines of symmetry Shapes with no lines of symmetry 3 Make a symmetrical pattern. 4 Which lines of symmetry are correct? Write the letters. b a c d 5 On which shapes can you draw a line of symmetry? Complete a table like this. Shape ✗ or ✓ Shape a b c d e f ✗ or ✓ 113 9781398300941_HCP_MATH_S2_LB.indb 113 2021/05/28 15:56 Unit 11 Shapes, direction and movement Practise (continued) 6 Part of each shape is missing. The dotted line is a line of symmetry. Copy each shape and complete it. b c a 7 Part of the picture is missing. The dotted line is a line of symmetry. Copy the picture and complete it. Try this Look at the symmetrical shape. Use 10 cubes to make your own symmetrical shape. Draw a picture of it. Let’s talk All rectangles have a line of symmetry. Is Viti correct? Explain your answer. 114 9781398300941_HCP_MATH_S2_LB.indb 114 2021/05/28 15:56 Unit 11 Shapes, direction and movement Position and movement Explore Where is the parrot? Maths words turn clockwise anticlockwise whole turn half turn quarter turn Learn A turn changes the direction you are facing. Your position stays the same. 115 9781398300941_HCP_MATH_S2_LB.indb 115 2021/05/28 15:56 Unit 11 Shapes, direction and movement Learn (continued) You can turn in different ways. You can turn clockwise and anticlockwise. Clockwise Anticlockwise You can turn in different amounts. You can do a whole turn, a half turn or a quarter turn. Whole turn Half turn Quarter turn A right angle is the same as a quarter turn. A quarter turn, clockwise You can turn shapes and objects. You can find right angles in many places. 90° 90° 90° 116 9781398300941_HCP_MATH_S2_LB.indb 116 2021/05/28 15:56 Unit 11 Shapes, direction and movement Learn (continued) Annay turns a square through a whole turn. The square looks the same 4 times. Try turning a rectangle through a whole turn. How many times does it look the same? Practise 1 Look at the shape. Annay turns the shape a quarter turn. Did he turn it clockwise or anticlockwise? b a Think of the hands of a clock. They move in a clockwise direction. 2 Look at the shape. Viti turns it clockwise. Did she turn it a half turn or a quarter turn? a b 117 9781398300941_HCP_MATH_S2_LB.indb 117 2021/05/28 15:56 Unit 11 Shapes, direction and movement Practise (continued) 3 Look at the shape: The teacher turns the shape: He turned it a quarter of a turn. He turned it half of a turn. Who is correct? 4 How many times does the shape look the same through a whole turn of the shape? b c d a rectangle pentagon equilateral triangle cross shape Try this Which shapes have right angles? How do you know? a b c d Let’s talk How many right angles can you find around the classroom? 118 9781398300941_HCP_MATH_S2_LB.indb 118 2021/05/28 15:56 Unit 11 Shapes, direction and movement Quiz 1 Copy each shape and draw a line of symmetry. a b c d e f 2 Draw the bee after each turn. a A quarter turn clockwise b A half turn anticlockwise 3 Which of these shapes have right angles? a b c 119 9781398300941_HCP_MATH_S2_LB.indb 119 2021/05/28 15:56 12 Fractions Equal parts Explore Folding is fun! Maths words fraction half halve quarter equal Fold a square of paper in half. Then fold it in half again. We can say that we halve the paper and then halve it again. What will you see when you unfold the paper? Try this with different shapes and sizes of paper. Learn Two of these 3 shapes are divided into equal parts. The equal parts are fractions of the whole shape. Two of these shapes are broken up into 4 equal parts. Each part is a quarter. One shape is not divided into equal fractions. Can you see why? One of the shapes is divided into 4 parts, but they are not equal. Can you see why? 120 9781398300941_HCP_MATH_S2_LB.indb 120 2021/05/28 15:56 Unit 12 Fractions Practise 1 Copy each shape and show one way to break up each shape into quarters. a b c d 2 a None of these shapes is broken up into quarters. Copy the table and sort the shapes. Not 4 parts Not equal parts b Explain why we can say: This shape is not divided into quarters. 3 Use 3 or more different lengths of string. Fold them in half, then in half again. Compare each quarter of the lengths of string. What do you notice? Explain what you see. Try this How many ways can you fold a square of paper into 4 equal parts? Experiment with different ways of folding. Can you make these shapes? Let’s talk Use tape, chalk or ropes to divide these school spaces into quarters: l the school hall l your desk l the playground. 121 9781398300941_HCP_MATH_S2_LB.indb 121 2021/05/28 15:56 Unit 12 Fractions Fractions of a group Explore The teams are ready to play! Learn You can find fractions of a group. Find half of 8 marbles. Half of 8 is 4. __ 12 of 8 is 4. Find a quarter of 8. So a quarter of 8 is 1 __ 4of 8 is . . 122 9781398300941_HCP_MATH_S2_LB.indb 122 2021/05/28 15:56 Unit 12 Fractions Practise 1 Use cubes or counters to find these. Draw your fractions to show the whole and the parts. 1 a __ 2 of 6 counters 1 b __ 2 of 12 counters 1 c __ 4of 20 counters 1 d __ 4of 16 counters 2 Write a fraction statement for each picture. b c a 3 Do you agree with Zara? Explain why this is wrong. Try this Which sets of books can we share into equal quarters? What do you notice? Can you continue the pattern? I have found a quarter because there are 4 cakes on each plate. A quarter of 12 cakes must be 4. Let’s talk Work out these pairs of fractions using counters or cubes. What do you notice? 1 __ 2 of 12 is 1 __ 4of 20 is __ 14of 12 is __ 12 of 40 is __ 12 of 20 is __ 41of 40 is 123 9781398300941_HCP_MATH_S2_LB.indb 123 2021/05/28 15:56 Unit 12 Fractions Quiz 1 Draw a picture of a shape broken up into quarters. 2 Draw a picture of a shape not broken up into quarters. 3 Explain why one shape shows quarters and the other does not. 4 Find a quarter of all the fish in the picture. Use cubes or counters to show how to solve this. 5 Choose a group of counters. Show whether you can break up the group into halves or quarters. 124 9781398300941_HCP_MATH_S2_LB.indb 124 2021/05/28 15:56 Term Review 2 Units 7–12 1 Choose pairs of numbers that total 20. 5 14 0 2 15 20 6 18 2 Find the totals. Think about the numbers you will add together first. a 3+4+7= b 6+5+5= c 1+9+4+3= d 3+1+8+2= 3 Draw 2 different ways to make each amount. a 15c b 40c c $35 4 Ask up to 10 children to stand in a line. Then ask them to wave gently with both hands. Count all the fingers in 5s. Now count in 10s. Is there an odd number or an even number of fingers? 5 How long is the pencil in centimetres? cm 6 Draw a line for each length. a 4 cm long b 8 cm long 125 9781398300941_HCP_MATH_S2_LB.indb 125 2021/05/28 15:56 Term 2 Review 7 Jack’s sunflower is 35 cm tall. Annay’s sunflower is 33 cm tall. b a 33 cm 35 cm How much taller is Jack’s sunflower? 8 This picture is symmetrical. Copy the picture and complete it. 9 Collect 20 counters. Sort them into equal halves. Then sort them into equal quarters. What is half of 20? What is a quarter of 20? 126 9781398300941_HCP_MATH_S2_LB.indb 126 2021/05/28 15:56 13 Statistical methods and chance Pictograms and block graphs Explore Look at all the different fish! How many blue fish? How many spotted fish? How many orange fish? How many blue, spotted and orange fish altogether? How many more orange fish than blue fish? Maths words tally chart pictogram block graph common category 127 9781398300941_HCP_MATH_S2_LB.indb 127 2021/05/28 15:56 Unit 13 Statistical methods and chance Learn We can make a tally chart. Fish Tally We can make a pictogram. Number of fish llll llll llll Pink fish llll llll llll Pink fish llll llll llll Blue fish Spotted fish Striped fish Yellow fish Stingray llll llll llll llll ll Blue fish llll lll l Spotted fish Striped fish Yellow fish Stingray We can make a block graph. Pink fish Blue fish Spotted fish Striped fish Yellow fish Stingray 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 How many pink fish did the diver see? How many yellow fish did the diver see? Which was the most common fish? Which was the least common fish? How many fish did the diver see altogether? 128 9781398300941_HCP_MATH_S2_LB.indb 128 2021/05/28 15:56 Unit 13 Statistical methods and chance Practise 1 This graph shows children’s favourite sports. y Block graph to show children’s favourite sports 12 Number of children 10 8 6 4 2 x 0 Tennis Football Cricket Favourite sports Cycling Archery a Which is the most popular sport? b Which is the least popular sport? c How many children like cycling? d How many more children like football than cycling? e How many more children like cricket than archery? f How many children answered the questions altogether? 129 9781398300941_HCP_MATH_S2_LB.indb 129 2021/05/28 15:56 Unit 13 Statistical methods and chance Practise (continued) 2 The table shows the number of T-shirts sold. Complete a table like this. Then answer the questions. Day Monday Tuesday Wednesday Thursday Friday Saturday Sunday Tally ll T-shirts 2 8 3 5 4 10 0 sold a How many T-shirts were sold on Friday? b On which day were the most T-shirts sold? c On which day were the least T-shirts sold? d How many T-shirts were sold on Saturday and Thursday? e How many T-shirts were sold in total? f Why do you think no T-shirts were sold on Sunday? g Draw a pictogram to show the data in the table. Try this Ask your friends what their favourite type of book is. Then create a block graph. I like reading animal stories. How will you collect the data? What categories or types of books will you choose? Let’s talk What do you think would happen if you did not pick categories before collecting data? Why is it important to pick categories before asking a question about collecting data? 130 9781398300941_HCP_MATH_S2_LB.indb 130 2021/05/28 15:56 Unit 13 Statistical methods and chance Venn diagrams and Carroll diagrams Explore How many different ways could you sort these animals? Which animals live in water? Maths words Venn diagram Carroll diagram Which animals have legs? Learn We use Venn diagrams and Carroll diagrams for sorting objects and numbers. Which shapes are circles? Which shapes are blue? 131 9781398300941_HCP_MATH_S2_LB.indb 131 2021/05/28 15:56 Unit 13 Statistical methods and chance Learn (continued) The shapes have been sorted in a Venn diagram. Blue Circle The shapes have been sorted in a Carroll diagram. Blue Not blue Circle Not a circle Practise 1 Complete a Carroll diagram like this. Red Not red 4 or more corners Not 4 or more corners 132 9781398300941_HCP_MATH_S2_LB.indb 132 2021/05/28 15:56 Unit 13 Statistical methods and chance Practise (continued) 2 a Copy the Venn diagram. 6 or bigger Even number 8 b Spin a spinner twice to get 2 numbers. Add the numbers. c Write the number on the Venn diagram. d Repeat to fill the diagram with more numbers. Try this Choose a two-digit number. Write your number on a blank Venn diagram. Repeat. Can your partner guess what your rules are? Let’s talk Talk to your partner. How could you sort the animals? What headings would you use in the Carroll diagram? 133 9781398300941_HCP_MATH_S2_LB.indb 133 2021/05/28 15:56 Unit 13 Statistical methods and chance Chance Explore Let’s play marbles! Maths words likely will not happen will happen might happen chance Use your conjecturing skills to answer these questions. Do you think Zara will pick a blue marble from the bag next? Do you think Viti will pick a red marble from the bag next? Who do you think will win? Play a game of marbles with a friend. Learn There are 4 red marbles and 4 green marbles in the bag. Annay picks a marble from the bag without looking. How likely is he to pick a red marble? It might happen. How likely is he to pick a marble? It will happen. How likely is he to pick a white marble? It will not happen. What chance does Annay have of picking a green marble? There are 4 green marbles and 8 in total, so he has 4 out of 8 chances of picking a green marble. 134 9781398300941_HCP_MATH_S2_LB.indb 134 2021/05/28 15:56 Unit 13 Statistical methods and chance Practise 1 David picks a counter from the bag. Use these words. It will not happen It might happen It will happen a How likely is it that he will pick an orange counter? b How likely is it that he will pick a blue counter? c How likely is it that he will pick a white counter? d How likely is it that he will pick a counter? 2 Look at each set of counters. Is there a pattern? Describe the pattern in your own words. a b c Try this Make sure you put Put 5 blue and 5 red counters the counter back in in a bag. Pick 1 but do not look. the bag each time. What colour could it be? How likely is it that it will be a blue counter, a red counter or a How could green counter? How likely is you record it? it that it will be a counter? Pick out 1 counter 10 times. What chance do you have You could of picking a red counter … keep a tally. and a blue counter? Let’s talk Use your skills of characterising. Can you think of some things that will happen today, that might happen today and that will not happen today? 135 9781398300941_HCP_MATH_S2_LB.indb 135 2021/05/28 15:56 Unit 13 Statistical methods and chance Quiz 1 Use this block graph to answer the questions. Number of flowers y 13 12 11 10 9 8 7 6 5 4 3 2 1 0 a How many red flowers were sold? b Which was the most popular colour? c Which was the least popular colour? d How many orange and white flowers were sold? e How many more orange flowers were sold than purple flowers? x f How many flowers were sold Red Purple Yellow White Orange altogether? Colour of flowers Flowers sold 2 Complete a Carroll diagram like this. Blue shapes 4 sides or more Not 4 sides or more Not blue shapes 3 Annay spins a 1 to 6 spinner. Answer each question with a statement. It will not happen It might happen It will happen How likely is it that he will spin: a a number? b the number 4? c the number 20? 136 9781398300941_HCP_MATH_S2_LB.indb 136 2021/05/28 15:56 14 Number patterns and place value Patterns and ordinals Explore Maths words pattern first, second, third, … 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 Viti makes a pattern. She continues like this. What shape will cover 99? What about the number 100? How do you know? 91 92 93 94 95 96 97 98 99 100 Learn Point to the people in the picture and say the position words: First, Second, Third, Fourth, Fifth, Sixth, Seventh, Eighth, Ninth, Tenth, Eleventh … 1st, 2nd, 3rd, 4th, 5th, 6th, 7th, 8th, 9th, 10th, 11th … Practise saying these position numbers: 21st, 22nd, 23rd, 24th, 25th, 26th, 27th, 28th, 29th, 30th, …. 137 9781398300941_HCP_MATH_S2_LB.indb 137 2021/05/28 15:56 Unit 14 Number patterns and place value Practise 1 Point to each place on the track. Say: 1st, 2nd, 3rd, … 2 What shape is: a 5th b 14th c 19th d twelfth e twenty-first? 3 a In what position are Annay, Viti and Jack standing? Annay is in position. Viti is in position. Jack is in position. b What shapes are they covering? 4 Later, Jack stands on the 45th square. Viti stands on the 50th square. What shapes are they covering? Try this You will need a blank 100 grid. Create your own repeating pattern of shapes on it. What would be in 25th, 75th and 99th position on your square? Invent your own patterns to challenge a partner. 138 9781398300941_HCP_MATH_S2_LB.indb 138 2021/05/28 15:57 Unit 14 Number patterns and place value Tens and ones Explore Maths words decompose compose What is the same? What is different? Learn We can decompose 24 into 2 tens and 4 ones. We can compose 3 tens and 2 ones to make 32. 24 32 20 4 This is 20 and 4. 20 + 4 = 24 30 2 30 and 2 make 32. 30 + 2 = 32 139 9781398300941_HCP_MATH_S2_LB.indb 139 2021/05/28 15:57 Unit 14 Number patterns and place value Practise 1 Decompose each number into tens and ones. a b 17 ? ? c ? ? d 42 ? ? 23 74 ? ? 2 Compose these parts to make wholes. b a ? 50 c 6 60 d ? 90 ? 9 7 ? 40 8 3 Complete these additions. a 20 + 5 = b 30 + 5 = c 40 + 5 = d e f 44 = 40 + = 40 + 5 = 50 + 4 g 90 + = 94 h i 4+ = 74 j 44 = 4 + + 4 = 84 140 9781398300941_HCP_MATH_S2_LB.indb 140 2021/05/28 15:57 Unit 14 Number patterns and place value Try this The number 31 has been regrouped in different ways. See how many different ways you can find to regroup these numbers. 32 41 70 Let’s talk No. I think it means 30 + 0, which is 30. I think this shows 300. ? 30 0 Do you agree with David or Viti? Discuss this with a partner. 141 9781398300941_HCP_MATH_S2_LB.indb 141 2021/05/28 15:57 Unit 14 Number patterns and place value Comparing and ordering numbers Explore What do you notice about the order of the shirts on the washing line? Maths words order compare What shirt number could be on the ground? Learn Choose a number line that will help you to put each set of numbers in order. Set A 35 32 40 24 is less than 28. 28 is greater than 24. Set B 39 24 9 70 Compare the number lines before choosing. What is similar? What is different? 20 30 30 40 0 10 20 30 40 50 60 70 80 90 100 142 9781398300941_HCP_MATH_S2_LB.indb 142 2021/05/28 15:57 Unit 14 Number patterns and place value Practise 1 Put the shirts in order. 2 Put each set of numbers in order from smallest to largest. 0 10 20 30 40 50 60 70 80 90 100 a 25, 14 b 26, 62, 4 c 72, 27, 5, 18 d 16, 61, 11, 39, 35 e 34, 12, 38, 26, 62 f 33, 37, 13, 63, 36 3 The table shows each child’s time of running a race. Child Zara David Viti Annay Jack Time 76 seconds 71 seconds 85 seconds 83 seconds 67 seconds a Who was first? b Who was second? c Who was third? d Zara finished between David and Annay. What was her time? Let’s talk 19 28 37 46 55 Use the number cards above to complete these sentences. is less than . is greater than . How many more number sentences can you make? 143 9781398300941_HCP_MATH_S2_LB.indb 143 2021/05/28 15:57 Unit 14 Number patterns and place value Round to the nearest 10 Explore How far can they throw? I got just over 20 m. 10 m 20 m 30 m I threw halfway between 30 m and 40 m. 40 m Maths word round Learn 24 rounds to 20 Look at the number 24. It is between 20 and 30. because it is nearer Is it nearer 20 or 30? 20 than 30. 20 30 Who do you agree with? 24 rounds to 30 because it is above 20. 29 is so close to 30 that it must round up. 25 is exactly halfway so we can’t decide. 144 9781398300941_HCP_MATH_S2_LB.indb 144 2021/05/28 15:57 Unit 14 Number patterns and place value Practise 1 Round each number to the nearest 10. Use the number track. 10 20 30 40 50 60 70 80 a 23 b 57 c d 41 e 98 f 66 g 82 h 25 i j 94 k 36 l 87 40 54 60 35 3 Round each number to38the nearest 10. 30 40 a 10s b 10s 1s 9 6 3 100 73 2 The arrows are pointing to different numbers. Write each number and round to the nearest 10. b a B C A B A 30 90 C 70 1s 4 d c 70 5 40 Try this Find all the possible answers. My number has 2 tens and some ones. It rounds to 30. 50 My number is even. It rounds to 70. My number is odd. It rounds up to 40. My number has 5 as one of the digits. It rounds to 50. 145 9781398300941_HCP_MATH_S2_LB.indb 145 2021/05/28 15:57 Unit 14 Number patterns and place value Let’s talk Use your critiquing skills. Talk to a partner about the diagram. How does it help to explain how to round numbers? 30 31 32 33 34 35 36 37 38 39 40 multiple of 10 multiple of 10 Quiz 1 Look at a 100 grid to answer these questions. a What is the 2nd even number? b What is the 21st odd number? 2 Decompose each number into tens and ones. a 41 b 57 c 80 3 a Use 0 to 9 digit cards to make 5 numbers between 10 and 100. b Put your numbers in order. 0 7 1 4 b ? 50 ? 40 ? 6 9 c ? 3 5 8 4 Each number rounds to 50. What are the missing parts? a 2 ? ? 9 146 9781398300941_HCP_MATH_S2_LB.indb 146 2021/05/28 15:57 15 Addition and subtraction Using mental strategies to add and subtract Explore The children are talking about different ways to solve calculations. We can use pairs that total 10 to help. We can count on to find the difference. Maths words calculation doubles difference We can also use what we know about doubles. And we can count in tens! Which calculation is each child talking about? Can they use their ideas for more than one calculation? Talk about other calculations you can solve in this way. 147 9781398300941_HCP_MATH_S2_LB.indb 147 2021/05/28 15:57 Unit 15 Addition and subtraction Learn We can use different mental strategies to help us add and subtract. Counting in tens helps us to add or subtract a number of tens. 56 + 20 = 76 + 10 + 10 + 56 50 55 76 66 60 56 – 10 = 46 65 70 75 – 10 46 40 45 56 50 55 60 We can use doubles to help us find near doubles. 4 1 + 3 3 3 = double 3 + 1 Practise 1 Write the missing numbers. a 36 – = 26 b 36 + = 46 36 – = 16 36 + = 56 36 – =6 36 + = 66 148 9781398300941_HCP_MATH_S2_LB.indb 148 2021/05/28 15:57 Unit 15 Addition and subtraction Practise (continued) c 45 – = 35 d 45 + = 55 45 – = 25 45 + = 65 45 – = 15 45 + = 75 2 Use doubles to help you calculate these. a 3+3+5= b 5+6= c 6+6+5+5= d 8+9= 3 Make a ten each time to help you calculate. a 7+6+3+2 b 1+8+9 c 5 + 4 + 10 + 5 d 8+9+1+2 4 Count up from the smaller number each time to find the difference. What do you notice? a 16 – 14 = b 26 – 24 = c 36 – 34 = 16 – 13 = 26 – 23 = 36 – 33 = 16 – 12 = 26 – 22 = 36 – 32 = Try this I cannot see any pairs that total 10. I will have to use another way to add. 5 + 7 + 2 + 1 4 + 5 + 1 8 + 1 + 6 + 1 3 + 4 + 2 + 3 What do you think? Can you help David to add the numbers? 149 9781398300941_HCP_MATH_S2_LB.indb 149 2021/05/28 15:57 Unit 15 Addition and subtraction Making estimates Explore It’s market day! The children are making estimates to see what they can buy. Maths words estimate more less I have 75 cents to spend. I have 50 cents to spend. I have 99 cents to spend. Does Zara have enough to buy 1 apple and 1 lemon? Which 2 items can Jack buy? Does Maris have enough money to buy any 2 items? Learn Jack wants to buy an orange for 45 cents and a lemon for 24 cents. Jack estimates: 45 rounds up to 50; 24 rounds down to 20. His estimate is: 50 + 20 = 70. Will the actual total be more or less than 70 cents? 45 + 24 = Work out the answer and check against Jack’s estimate. 150 9781398300941_HCP_MATH_S2_LB.indb 150 2021/05/28 15:57 Unit 15 Addition and subtraction Practise 1 A banana costs 52 cents. Estimate the total cost for: a 1 apple and 1 banana b 1 orange and 1 banana c 1 banana and 1 lime d 2 bananas 2 Make an estimate each time. a 32 + 51 = b 68 – 42 = c 23 + 76 = d 94 – 52 = e Now calculate and check the answer against your estimate. Try this Use estimates to sort these subtractions by their answers: Less than 30 Between 30 and 60 More than 60 76 – 32 98 – 77 43 – 22 62 – 9 38 – 19 84 – 19 Will the actual answer be more or less each time? Make up another subtraction for each group. Let’s talk Zara is finding answers to some additions. 48 + 36 = 37 + 34 = 41 + 38 = She uses rounding to make estimates first. Her estimate is 70 because 40 + 30 = 70 Which of the 3 additions match her estimate? Now make estimates for her other additions. Talk about the methods you use. 151 9781398300941_HCP_MATH_S2_LB.indb 151 2021/05/28 15:57 Unit 15 Addition and subtraction Adding pairs of two-digit numbers Explore Maths word decompose 5 6 7 8 9 10 11 12 13 14 18 19 20 2 1 4 16 0 3 17 The children are playing a game. 27 22 23 24 25 26 28 37 38 39 40 41 42 43 45 4 48 6 47 36 32 33 34 35 44 49 29 30 31 50 Help Viti to move her counter on to match the total of the 3 numbers that she spins. How much does she add in total? Now help Jack to move his counter. How much does he add in total? 152 9781398300941_HCP_MATH_S2_LB.indb 152 2021/05/28 15:57 Unit 15 Addition and subtraction Learn We can add two-digit numbers in another way. 35 + 24 = Decompose the numbers into tens and ones. 35 35 24 24 There are 3 tens and and 5 ones. 2 tensare and 2 4 ones. There are 3 tens 5 ones.There areThere tens and 4 ones. Add the tens: 3 tens + 2 tens = 5 tens 30 + 20 = 50 Add the ones: 5 ones and 4 ones = 9 ones 5 + 4 = 9 Add these together: 50 + 9 = 59 The answer is 59. 35 + 24 = 59 153 9781398300941_HCP_MATH_S2_LB.indb 153 2021/05/28 15:57 Unit 15 Addition and subtraction Practise 34 1 Use cubes to help you complete these additions. + 23 is a different way of 22 + 15 = a 25 + 12 = writing 34 + 23. 35 + 12 = b 34 + 23 32 + 15 = 34 + 25 44 + 23 44 + 25 2 Draw number lines to help you complete these additions. Look at the example. + 10 35 + 22 = 57 + 10 35 +2 57 a 35 + 23 = b 42 + 21 = c 42 + 23 = d 42 + 25 = 3 The stall holder buys 23 oranges and 45 passion fruits from the farmer. How many fruits does she have in total? First make an estimate. Try this + Let’s talk 4 5 2 1 6 6 Find at least 3 other additions like this with the answer 66. Look together at the additions and your answers for Practise question 1b. What patterns do you notice? Try to continue any patterns you find. 154 9781398300941_HCP_MATH_S2_LB.indb 154 2021/05/28 15:57 Unit 15 Addition and subtraction Subtracting two-digit numbers Maths word subtract Explore A shop sells these items. 10 cups 10 cups 10 cups 10 cups 10 glasses 10 glasses 10 glasses 10 glasses There are more cups than glasses. How many more? The shop sells 15 cups. How many are left on the shelf? The shop also sells some of the boxes of glasses and 3 of the single glasses. How many glasses could be left on the shelf? Learn The cubes show the total number of cups on the shelf. The shop sells 15 cups, so we subtract a 10 and 5 ones. There are 32 cups left. We can write 47 – 15 = 32 or 47 – 15 32 We can do the same calculation on the number line. –5 – 10 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 We count back 10 and then use the subtraction fact 7 – 5 = 2 to take away the ones. 155 9781398300941_HCP_MATH_S2_LB.indb 155 2021/05/28 15:57 Unit 15 Addition and subtraction Practise 1 Use cubes to help you solve these subtractions. a 45 – 13 = b 58 – 22 = 45 – 23 = 58 – 32 = 45 – 33 = 58 – 42 = 45 – 43 = 58 – 52 = c 57 – 24 67 – 34 Look for numbers that are close together. Sometimes it is easier to count on to find the difference. 77 – 44 87 – 54 2 Complete these subtractions by counting back on the number line. Look at the example. 77 – 22 = 55 –2 – 10 55 57 – 10 67 77 a 87 – 24 = b 97 – 26 = c 65 – 34 = d 55 – 23 = e 45 – 12 = f 76 – 31 = 3 Complete these. Which method will you use this time? a 27 – 26 = b 65 – 64 = c 18 – 17 = 27 – 25 = 65 – 63 = 18 – 16 = 27 – 24 = 65 – 62 = 18 – 15 = 156 9781398300941_HCP_MATH_S2_LB.indb 156 2021/05/28 15:57 Unit 15 Addition and subtraction Try this I am using the number line to calculate 39 – 16. –6 – 10 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 I think Annay has made a mistake. What mistake has Annay made? Draw a number line to show the correct answer. Let’s talk The answer to 56 – 24 is about 30 because 50 – 20 = 30. The answer is about 40 because 60 – 20 = 40. The answer is between 30 and 40. What did the children do to make their estimates? Can you use the children’s ideas to estimate the answer to 48 – 33? 157 9781398300941_HCP_MATH_S2_LB.indb 157 2021/05/28 15:57 Unit 15 Addition and subtraction Addition and subtraction facts to 100 Explore It is a busy day in the city. Many people use the bus to travel from place to place. More than 20 people get off the bus. The same number get on the bus. How many people could be on the bus now? Explain your thinking. Maths word inverse Learn To start with, there are 36 people on a bus. Look what happens when 22 people get off the bus. –2 – 10 – 10 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 We write: 36 – 22 = 14. There are 14 people left on the bus. The same number of people get on the bus. We write: 14 + 22 = + 10 + 10 +2 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 What is the same and what is different about the 2 number lines? 14 + 22 = 36 is the inverse addition sentence for 36 – 22 = 14. What is the inverse subtraction sentence for 14 + 22 = 36? 158 9781398300941_HCP_MATH_S2_LB.indb 158 2021/05/28 15:57 Unit 15 Addition and subtraction Practise 1 Write the inverse addition sentence for each subtraction. a 25 – 13 = 12 b 36 – 16 = 20 c 49 – 27 = 22 d 55 – 24 = e 67 – 36 = f 79 – 48 = 2 True or false? a 45 + 12 = 57 so 45 – 12 = 57 b 56 + 23 = 79 so 23 – 79 = 56 c 67 + 31 = 98 so 98 – 31 = 67 3 Write a number sentence to match each number story. a There are 35 people on a bus. 14 more get on. Then 14 get off. b There are 47 people on a bus. 24 get off. Then 24 more get on. Try this Look at these bar models. Find the 2 addition sentences and the subtractions for each bar model. 75 50 25 20 80 60 93 51 42 Let’s talk I think you can use an inverse subtraction sentence to check an addition. What do you think? Try out some examples. How can David check a subtraction? Explain your idea. 159 9781398300941_HCP_MATH_S2_LB.indb 159 2021/05/28 15:57 Unit 15 Addition and subtraction Quiz 1 Complete these calculations. a 10 + 53 = 20 + 53 = 30 + 53 = b 84 – 10 = 84 – 20 = 84 – 30 = c 67 – 63 = 57 – 53 = 47 – 43 = d 33 + 33 = 33 + 34 = 33 + 32 = 2 Complete these additions. Make an estimate first. c 62 a 43 + 26 = ? + 27 b 55 + 32 = ? ? 3 Complete these subtractions. Make an estimate first. c 67 a 46 – 23 = ? – 25 b 59 – 32 = ? ? 4 Write the inverse subtraction sentences each time. a 43 + 22 = 65 b 35 + 21 = 56 c 54 + 32 = 86 5 Write the inverse addition sentences each time. a 46 – 25 = 21 b 75 – 32 = 43 c 68 – 45 = 23 160 9781398300941_HCP_MATH_S2_LB.indb 160 2021/05/28 15:57 16 Multiplication and division Multiplication as doubling Explore Monday Tuesday Wednesday Thursday Friday Each day, Jack catches twice as many fish as the day before. How many fish does he catch on Thursday and Friday? Maths word doubles 161 9781398300941_HCP_MATH_S2_LB.indb 161 2021/05/28 15:57 Unit 16 Multiplication and division Learn ×2 two lots of double 2 groups of twice Double Counters Double 1 As an addition 1+1=2 As a As a multiplication division 1×2=2 2÷2=1 Double 2 2+2=4 2×2=4 4÷2=2 Double 3 3+3=6 3×2=6 6÷2=3 Double 4 4+4=8 4×2=8 8÷2=4 Double 5 5 + 5 = 10 5 × 2 = 10 10 ÷ 2 = 5 Double 6 6 + 6 = 12 6 × 2 = 12 12 ÷ 2 = 6 Double 7 7 + 7 = 14 7 × 2 = 14 14 ÷ 2 = 7 Double 8 8 + 8 = 16 8 × 2 = 16 16 ÷ 2 = 8 Double 9 9 + 9 = 18 9 × 2 = 18 18 ÷ 2 = 9 Double 10 10 + 10 = 20 10 × 2 = 20 20 ÷ 2 = 10 Try to learn these doubles facts! 162 9781398300941_HCP_MATH_S2_LB.indb 162 2021/05/28 15:57 Unit 16 Multiplication and division Practise 1 Write the answers to these doubles. See the example. + a = 2 glasses of juice + + c = = + ++ = b ++ = += d= + =+= = == = 2 How many counters are there in each picture? Write a number sentence to match. a b c d e 3 Complete the addition sentences. a 2+2= × b 5+5= c 6+6= × d 10 + 10 = × × Let’s talk You know that double 10 is 20 and double 3 is 6. How does that help you to find double 13? How can you use double 10 and other doubles you know to find: double 11 ? double 12 ? double 14 ? double 15 ? 163 9781398300941_HCP_MATH_S2_LB.indb 163 2021/05/28 15:57 Unit 16 Multiplication and division Multiplication tables of 1 and 2 Explore What is different about the 2 cycles? How many wheels are on 3 monocycles? What do you notice about the number of monocycles and the number of wheels? Maths words repeated addition multiplication times table Learn This number line shows the number of wheels on three bicycles. The number line shows the number of wheels on three monocycles. +1 0 +1 1 +1 2 +2 3 4 5 0 +2 2 +2 4 6 Repeated addition can help us to write the multiplication tables. 1×1=1 1×2=2 1×3=3 1×4=4 1×5=5 1 1+1 1+1+1 1+1+1+1 1+1+1+1+1 This is part of the 1 times table. 2×1=2 2×2=4 2×3=6 2×4=8 2 × 5 = 10 2 2+2 2+2+2 2+2+2+2 2+2+2+2+2 This is part of the 2 times table. I can see some doubles! 164 9781398300941_HCP_MATH_S2_LB.indb 164 2021/05/28 15:57 Unit 16 Multiplication and division Practise 1 Complete the multiplication tables. Use repeated addition to help you. 2 Write the multiplication fact to match each sentence. 1×1= 2×1= a 3 groups of 1 is 1×2= 2×2= b 4 groups of 2 is 1×3= 2×3= c 5 groups of 1 is 1×4= 2×4= d 6 groups of 2 is 1×5= 2×5= 1×6= 2×6= 1×7= 2×7= 1×8= 2×8= 1×9= 2×9= 1 × 10 = 2 × 10 = Try this True or false? 1×4=2×2 Can you make other number sentences like this using multiplication facts you know? 3 2 × 5 = 10 Which division sentence also tells us that there are 5 groups of 2 in 10? 2 ÷ 10 = 5 10 ÷ 1 = 10 10 ÷ 2 = 5 10 ÷ 10 = 1 Let’s talk I have 7 bags with 1 apple in each. There are 7 apples. I have 7 bags with 2 apples in each. I have double the number of apples as David! Do you agree with Zara? Draw or write something to convince your partner. 165 9781398300941_HCP_MATH_S2_LB.indb 165 2021/05/28 15:57 Unit 16 Multiplication and division Multiplication tables of 5 and 10 Explore The children are making trains with blocks. What can the totals of their trains be? How many blocks must they each use for the totals to be the same? What do you notice? 10 5 5 5 5 5 5 5 10 10 10 10 5 5 5 10 10 10 10 10 Learn We can use the fives blocks and repeated addition to help build the 5 times table. 5×1=5 5 5 × 2 = 10 5 5 5 × 3 = 15 5 5 5 5 × 4 = 20 5 5 5 5 How does the pattern continue? We can also use the tens blocks to help build the 10 times table. 10 × 1 = 10 10 10 × 2 = 20 10 10 10 × 3 = 30 10 10 10 10 × 4 = 40 10 10 10 10 How does the pattern continue? 166 9781398300941_HCP_MATH_S2_LB.indb 166 2021/05/28 15:57 Unit 16 Multiplication and division Practise 1 Complete and compare the multiplication tables. 2 Write the multiplication fact to match each sentence. 5×1= 10 × 1 = a 5×2= 10 × 2 = b 3 groups of 10 is 5×3= 10 × 3 = c 5×4= 10 × 4 = d 6 groups of 10 is 5×5= 10 × 5 = 5×6= 10 × 6 = 5×7= 10 × 7 = 5×8= 10 × 8 = 5×9= 10 × 9 = 5 × 10 = 10 × 10 = 3 groups of 5 is 6 groups of 5 is 3 aOne bucket holds 5 litres of water: What is the total for 3 buckets? b One box holds 10 kg of rocks: What is the total for 5 boxes? What is the total for 10 boxes? Try this Let’s talk Jack has some 10 cent coins. Viti has some 5 cent coins. The children have an equal number of cents in total. Find different ways to make this true. What patterns do you notice? Make up some word problems to match these multiplication facts. 5 × 7 = 35 10 × 6 = 60 Convince another pair that your word problems match. 167 9781398300941_HCP_MATH_S2_LB.indb 167 2021/05/28 15:57 Unit 16 Multiplication and division Using arrays Explore The children are visiting the animal sanctuary shop. There are many things to buy. Postcards $2 Maths word array $10 Badges $1 $5 $5 What do you notice about the way the items are arranged? How many are there of each item? How much will it cost to buy 2 of each item? 168 9781398300941_HCP_MATH_S2_LB.indb 168 2021/05/28 15:57 Unit 16 Multiplication and division Learn At the animal sanctuary, each penguin eats 2 fish. How many fish will the sanctuary volunteer need if there are 4 penguins? 2×4 ⎫ A pair of penguins being fed fish ⎪ by a sanctuary volunteer ⎬ The array shows 8 fish. ⎪ 2×4=8 ⎭ This is one of the facts in the 2 times table. Practise 1 Each penguin eats 2 fish. Use the arrays to work out how many fish the volunteer will need each time, for: b 6 penguins a 5 penguins 2×5= 2×6= c 7 penguins d 8 penguins 2×7= 2×8= 169 9781398300941_HCP_MATH_S2_LB.indb 169 2021/05/28 15:57 Unit 16 Multiplication and division Practise (continued) 2 Each monkey eats 5 bananas. Draw an array and write a matching multiplication sentence. Show how many bananas the volunteer will need each time. a 2 monkeys will need: 5 × 2 = b 3 monkeys will need: 5 × 3 = Remember, you should also think about the multiplication tables that you know! c 4 monkeys will need: 5 × 4 = d 5 monkeys will need: 5 × 5 = e 6 monkeys will need: 5 × 6 = 3 The children line up in 4 rows of 10 to visit the sanctuary. How many children in total? Write the multiplication sentence. Try this Let’s talk Use the array to complete the multiplication sentence: × = × How could you change the array to show 10 × 2 = 20? How many different arrays can you make with 30 counters? Use your skill of specialising. Write a multiplication sentence each time. 170 9781398300941_HCP_MATH_S2_LB.indb 170 2021/05/28 15:57 Unit 16 Multiplication and division Sharing for division Explore Maths words share equal division divide Viti is playing Animal snap with 20 cards. How many cards does Viti have when she plays on her own? The other children join in one at a time. They share the cards so they each get an equal number. What happens? Learn 20 ÷ 4 We can use sharing for division. If we divide or share 20 equally between 4 groups, we get 5. 20 5 5 5 5 That’s the same as finding quarters! 171 9781398300941_HCP_MATH_S2_LB.indb 171 2021/05/28 15:57 Unit 16 Multiplication and division Practise 1 Use sharing for division. Explain your method to a friend. a 10 ÷ 2 = b 10 ÷ 5 = c 10 ÷ 10 = d 40 ÷ 4 = e 40 ÷ 5 = f 40 ÷ 10 = 2 Write the matching division sentences. Explain how you know. a b 16 16 c 25 d 50 3 Which is the odd one out? Explain your decision. 18 ÷ 2 90 ÷ 10 8 ÷ 1 45 ÷ 5 Try this Viti has 2 packs of 20 animal cards. She invites some friends to play. How many friends could play a game so they each have the same number of cards? All the cards need to be used. Let’s talk 10 ÷ 1 = I think the answer is 1 because there will only be one group. I think the answer is 10 because there are no other groups to share 10 between. Do you agree with Annay or Maris? Discuss with a partner. 172 9781398300941_HCP_MATH_S2_LB.indb 172 2021/05/28 15:57 Unit 16 Multiplication and division Grouping for division Explore It’s a beautiful day for a balloon ride. What different number sentences can you make about the picture? What if 100 people went on a balloon ride that day? How many balloons would there be? Learn There is 1 group of 10 people in each balloon. There are 5 groups of 10 in 50 because 10 × 5 = 50. 50 divided into groups of 10 is 5. 50 ÷ 10 = 5 50 10 10 10 10 10 173 9781398300941_HCP_MATH_S2_LB.indb 173 2021/05/28 15:57 Unit 16 Multiplication and division Practise 1 Complete these divisions. Explain your method each time. a 8÷1= 7÷1= 6÷1= b 16 ÷ 2 = 14 ÷ 2 = 12 ÷ 2 = c 40 ÷ 5 = 35 ÷ 5 = 30 ÷ 5 = d 80 ÷ 10 = 70 ÷ 10 = 60 ÷ 10 = Think about the multiplication facts you know. 2 Write number sentences. Explain your method each time. a There are 18 sandbags. Each balloon has 2 sandbags. How many balloons are there? b There are 60 blankets. Each balloon has 10 blankets. How many balloons are there? c There are 45 pairs of binoculars. Each balloon has 5 pairs. How many balloons are there? Try this Look at Zara’s division. Do you agree with her? Explain your thinking. Correct Zara’s work if you think she is wrong. 35 ÷ 5 = 6 I know that 5 x 6 = 35, so there are 6 fives in 35 Let’s talk Use your skill of classifying. Which of these numbers can you group in twos? 25, 16, 40, 9 Talk about the numbers that you can group in fives or in tens. What do you notice? Which number is the odd one out? Why? 174 9781398300941_HCP_MATH_S2_LB.indb 174 2021/05/28 15:57 Unit 16 Multiplication and division Division as repeated subtraction Explore Different animals are together at a watering hole. Maths words repeated subtraction Soon all the animals will be gone. How many groups of animals leave the watering hole when they walk away in: l ones? l twos? l fives? l tens? Learn We can use repeated subtraction to show the animals walking away from the watering hole. What does this number line show us? 0 5 10 How many animals walk away in each group? How many groups are there? Write this as a division sentence. 175 9781398300941_HCP_MATH_S2_LB.indb 175 2021/05/28 15:57 Unit 16 Multiplication and division Practise 1 Imagine 20 animals at the watering hole. How many groups leave the watering hole when the animals walk away in: a ones? b twos? c fours? d fives? e tens? 2 Write each division as a repeated subtraction. Look at the example. 15 ÷ 5 = 3 15 – 5 – 5 – 5 = 0 a 25 ÷ 5 = 5 b 30 ÷ 10 = 3 d 6÷2=3 c 50 ÷ 10 = 5 e 10 ÷ 2 = 5 3 Write the matching repeated subtraction sentence: There are 18 gloves in a basket. How many children can take a pair? Try this ÷ How many ways can you make this true? =4 Make up a repeated subtraction number story to match one of your solutions. Let’s talk Maris uses repeated subtraction to solve a division: – – – = 0 What could the division be? Work together to find at least 3 solutions. 176 9781398300941_HCP_MATH_S2_LB.indb 176 2021/05/28 15:57 Unit 16 Multiplication and division Quiz 1 Complete these sets of multiplications. a 1×3= b 2×3= 1×4= 2×4= 1×5= 2×5= c 5×5= d 10 × 5 = 5×6= 10 × 6 = 5×7= 10 × 7 = 2 Sketch an array for each of these. Write the total each time. a 5×3 b 2×6 c 10 × 4 3 At a school, 8 teams have 5 players each. How many players are there in total? 4 Write the division number sentence each time. a The teacher puts 20 children into teams of 5. How many teams are there? b How many groups of 10 can you take from 90? c There are 16 oranges in a box. Elok shares them equally between 2 children. How many oranges does each child get? 177 9781398300941_HCP_MATH_S2_LB.indb 177 2021/05/28 15:57 17 Fractions Divide to find fractions Explore What is the whole? This is half of my shape. This is one quarter of my shape. Maths word one quarter Learn Divide 6 by 2 Find half of 6 I will share 6 between 2. Compare these problems: 12 ÷ 4 = Find __ 14of 12. I will use 6 counters. But is my problem like yours? 1 __ 4is one quarter. 178 9781398300941_HCP_MATH_S2_LB.indb 178 2021/05/28 15:57 Unit 17 Fractions Practise 1 Solve these fraction problems using cubes, counters and drawings. 1 a Find __ 2 of 10. c 1 __ 4of 12 is b What is __ 12 of 16? . 1 d __ 4of 8 is . 2 There are 16 children in a class. Divide them into 4 equal teams. Write your answer as a fraction number sentence. 3 Complete the missing information. 1 a __ 2 of is 5. 1 b __ 4 of 1 c __ 2 of is 2. d is 5. of 4 is 1. Try this Explore the whole numbers up to 20. Which whole numbers can you divide into halves? Which whole numbers can you divide into quarters? Let’s talk Are all these shapes broken up into quarters? Discuss this with a partner. 179 9781398300941_HCP_MATH_S2_LB.indb 179 2021/05/28 15:57 Unit 17 Fractions One quarter, two quarters, three quarters … Explore Think about equal parts. Draw one of these shapes. Colour in 2 equal parts. What fraction have you coloured in? Learn Place fractions on a number line. Where does half go? 1 2 3 4 __ __ __ __ 0 4 4 4 4 1 Compare two quarters and one half ( __ 2 ). They are equivalent. 1 __ 4 2 __ 4 3 __ 4or three quarters 4 __ 4 1 __ 2 Which fraction is less than one half? Which fraction is greater than one half? Maths word two quarters equivalent three quarters 180 9781398300941_HCP_MATH_S2_LB.indb 180 2021/05/28 15:57 Unit 17 Fractions Practise 1 a Draw a number line from 0 to 1. b Label it with quarters and halves in the correct places. 2 a Say the name of each fraction. 1 __ 2 __ b Find a pair of equivalent fractions. 4 4 4 __ 1 __ c Write the fractions in order. 4 2 3 __ 4 3 First Viti painted 1 half yellow. Then Zara painted 1 more quarter blue. a What fraction is painted? b What fraction is not painted? 4 Copy each shape. a b Colour half of each shape yellow. Colour 1 more quarter of each shape blue. c d What fraction have you shaded? What fraction is left blank? Try this Practise counting from 0 to 1 in quarters. Draw a number line to help you. Try counting forwards and backwards. 2 1 __ instead of Try saying __ 4 2 when you count. Quiz 1 1 Find __ 4of each number: a 8 b 12 c 20 2 Draw one quarter, two quarters, and three quarters. 181 9781398300941_HCP_MATH_S2_LB.indb 181 2021/05/28 15:57 18 Time and measurement Time Maths words calendar day week month year Explore The calendar shows the month of July. What is happening in July? JULY Sunday Monday Tuesday Wednesday Thursday Friday Saturday 1 2 3 4 5 6 8 7 Jade’s party Jade’s birthday 9 10 11 12 13 14 Gran 15 coming to stay 16 17 18 Sports day 19 20 21 22 23 24 25 26 27 28 29 Haircut 30 Dentist 31 182 9781398300941_HCP_MATH_S2_LB.indb 182 2021/05/28 15:57 Unit 18 Time and measurement Learn rN ctobe ovembe O r r be Saturda y January Feb mber e c ru e D ugust Sep uly A tem eJ un ay Wed sd y day Monday T n u ue S There are 52 weeks and 12 months in a year. h Apri l M a Marc yJ ary There are 7 days in a week. There are 24 hours in a day. There are 60 minutes in an hour. There are 60 seconds in a minute. y Thursday Fri da sda ne Practise The calendar shows the month of January. 1 Which day comes after Wednesday? JANUARY 2 Which day comes after Friday? SUN MON TUES WED THU FRI SAT 3 Which day comes before Monday? 1 2 3 4 4 Which day comes before Friday? 5 6 7 8 9 10 11 5 Which month comes after January? 6 Which month comes before January? 12 13 14 15 16 17 18 19 20 21 22 23 24 25 7 Which month comes after June? 26 27 28 29 30 31 8 Which month comes before June? Let’s talk What day of the week is it today? What day will it be in 10 days? How could you work it out? Which month of the year is it now? What month will it be in 6 months? How can you check? 183 9781398300941_HCP_MATH_S2_LB.indb 183 2021/05/28 15:57 Unit 18 Time and measurement Capacity Explore David, Annay and Zara water the plants. They each use 4 litres of water. Maths words litres capacity measuring cylinder measuring scale millilitres Annay fills his watering can 4 times. Zara fills her watering can twice. David fills his watering can once. How much water does each watering can hold? 184 9781398300941_HCP_MATH_S2_LB.indb 184 2021/05/28 15:57 Unit 18 Time and measurement Learn Capacity is the amount that a container can hold. We can measure capacity by counting how many cups of water fill a container. The cups must be the same size and shape. Remember to fill the cup each time. Remember that you can only compare containers if you measure them in the same way. The bowl holds 2 cups. The jug holds 3 cups. The bucket holds 4 cups. It holds the most water. It has the largest capacity. We can also measure capacity using a measuring cylinder. It has marks or lines to show you how much is in it. We call these lines a measuring scale. A measuring scale is similar to a continuous number line where the in-between marks have values. 185 9781398300941_HCP_MATH_S2_LB.indb 185 2021/05/28 15:57 Unit 18 Time and measurement Learn (continued) We measure capacity in litres (ℓ) and millilitres (ml). We use the symbol ℓ for litres. We use the symbol ml for millilitres. We use measuring jugs and measuring cylinders to measure the capacity of containers. The water level in the measuring jug is at the 300 ml mark. The measuring jug holds 300 ml of water. ml Using the symbols makes it quick and easy to write the measurement. 450 350 250 150 50 500 400 300 200 100 Practise 1 Use a table like this. Fill in the answers to the questions. Container Estimate Number of cups __________________________________________________________________ watering canwatering watering can watering can can watering can jam jar jam jar jam jam jar jam jar jar jug jug jug water jug water water bottle bottle jug water bottlebottle water bottle a Estimate which container holds the most water. b Find out exactly how many cups of water each container holds. How will you do this? 186 9781398300941_HCP_MATH_S2_LB.indb 186 2021/05/28 15:57 Unit 18 Time and measurement Practise (continued) 2 Which container holds the most water? 3 Which container holds the least water? 4 Put the containers in order from: holds the least to holds the most. 5 Estimate each time. a How many jam jars of water will fill the watering can? b How many bottles of water will fill the jug? c Does the watering can or the jug hold the most water? 6 How much water is in each measuring container? a ml 500 450 350 250 150 50 b ml 500 450 400 350 300 400 300 It is important to measure correctly. 200 100 Put the measuring container on a flat surface. Use a table or counter. Never just hold it in your hand! 250 200 150 100 50 c ml 500 Always measure at eye level, looking straight at it. Bend down if you need to. 450 400 350 300 250 200 150 100 50 Pour in the liquid until it is exactly at the measuring line, not above or below it. 187 9781398300941_HCP_MATH_S2_LB.indb 187 2021/05/28 15:57 Unit 18 Time and measurement Practise (continued) 7 Copy the number sentences. Use <, > or = to compare amounts. a 100 ml c 3ℓ 50 ml b 100 ml d 2ℓ 1ℓ 150 ml 1ℓ 8 Use <, > or = to compare the amounts. b a 450 350 250 150 50 250 ml 250 ml 250 ml 250 ml 300 ml 300 ml c 500 400 300 200 100 500 500 ml ml 250 ml d 300 ml 300 300ml ml 200 200200 ml ml ml 300 mlml 300 300 ml 200 ml Let’s talk I think the measuring cylinder has the largest capacity. It is the tallest. Is Jack correct? Explain why or why not. measuring cylinder bottle cup 188 9781398300941_HCP_MATH_S2_LB.indb 188 2021/05/28 15:57 Unit 18 Time and measurement Measures Explore Can you name these measuring instruments? What could you use each measuring instrument to measure? 189 9781398300941_HCP_MATH_S2_LB.indb 189 2021/05/28 15:57 Unit 18 Time and measurement Learn Measurement Measuring instrument Unit Length Centimetres Metres Kilometres Mass Grams Kilograms Capacity Millilitres Litres 190 9781398300941_HCP_MATH_S2_LB.indb 190 2021/05/28 15:57 Unit 18 Time and measurement Practise 1 Annay is baking a cake. Which measuring instrument should he use to weigh the butter? a b c 2 Zara is measuring the length of the classroom. Which measuring instrument should she use? a b c 3 Jack is measuring out some water. Which measuring instrument should he use? a b c 191 9781398300941_HCP_MATH_S2_LB.indb 191 2021/05/28 15:58 Unit 18 Time and measurement Practise (continued) 4 How long is each pencil? a b 5 How heavy is each letter? What is its mass? a b Let’s talk Match each measuring instrument a to the correct unit of measurement. c centimetres metres millilitres b d grams What could you use each measuring instrument to measure? 192 9781398300941_HCP_MATH_S2_LB.indb 192 2021/05/28 15:58 Unit 18 Time and measurement Quiz 1 Which month comes after February? 2 Which day comes before Tuesday? 3 Which month is after July? 4 Which month is before April? 5 How much water is in the measuring cylinder? ml 500 450 400 350 300 250 200 150 100 50 6 Copy these capacity sentences and fill in the <, > or = signs to compare the amounts. a 5 litres 10 litres b 400 ml 300 ml c 5 litres 1 litre 7 Write which instrument you would use to do these things. a Measure the length of a piece of ribbon. b Weigh a parcel. c Measure an amount of water. 193 9781398300941_HCP_MATH_S2_LB.indb 193 2021/05/28 15:58 Term 3 Review Units 13–18 Even numbers 1 Complete a Venn diagram, like the one on the right. Use these numbers: 23, 42, 4, 6, 12, 28, 31 2 Viti spins a 1 to 6 spinner. How likely is it that she: a spins and gets a number? b spins and gets an 8? c spins and gets a 3? Choose from these words to answer each time. It will not happen 1 20 or more 2 6 3 5 4 It might happen It will happen 3 How many children are in your class today? Round the number to the nearest 10. 4 Find the missing numbers. Then write the inverse calculation sentences. a 100 – 30 = b 60 + = 100 c d 90 – = 60 50 + 20 = 5 Complete these calculations. a 52 + 23 = b 52 + 25 c 66 – 25 d 68 – 25 = 194 9781398300941_HCP_MATH_S2_LB.indb 194 2021/05/28 15:58 Term 3 Review 6 Complete these divisions. 16 ÷ 2 = b 30 ÷ 5 = c 60 ÷ 10 = d 25 ÷ 5 = a 7 Fill in the missing numbers in these multiplication facts. a 2× =8 b 5× c 10 × = 50 d × 9 = 18 × 9 = 45 f × 10 = 100 e = 15 8 Draw a number line to show one quarter, two quarters, three quarters, 0 and 1. Explain where half is on the number line. 9 Viti is measuring the length of a table. Which measuring instrument should she use? a c b 10 How much water is in each jug? a 1000 ml b 1000 ml 195 9781398300941_HCP_MATH_S2_LB.indb 195 2021/05/28 15:58 Mathematical dictionary 2D shapes two-dimensional geometric shapes; flat shapes with sides and angles circle triangle square rectangle pentagon hexagon 3D shapes three-dimensional geometric shapes; solid shapes with faces, edges and corners; see also face, edge and corner cube sphere cuboid triangular prism cone cylinder square-based pyramid A addition a calculation of the sum of two numbers or things amount the total of things such as numbers, size or value anticlockwise in the opposite direction to the hands of a clock array an arrangement made up of rows and columns B block graph a diagram to show information C calculation a way of finding the number of something calendar a chart or pages that show the months and days of a whole year capacity the largest amount that something can contain Carroll diagram a table used for sorting things Multiple of 5 Not a multiple of 5 10, 20, 30 2, 6, 12 Not an even 5, 15, 25 number 3, 7, 11 Even number category a division, class or certain type of thing; music has categories such as hip hop, folk, blues, pop cent(s) a coin value centimetre (cm) there are 100 centimetres in a metre chance a possibility of something happening clockwise in the same direction as the hands of a clock coin a piece of metal used as money 196 9781398300941_HCP_MATH_S2_LB.indb 196 2021/05/28 15:58 Mathematical dictionary common happens often compare to note similarities and differences complement(s) the amount you must add to something to make it a whole compose to combine place value parts, for example: 200 + 40 + 2 = 242 corner where two or more lines meet and form an angle count to use numbers to see how many there are of something curved round, not straight D data information that has been collected in some way day there are 24 hours in a day; a day is one of the 7 days in a week decompose separate a number into each of its place value parts 24 20 4 difference the answer when subtracting one number from another divide to find how many times a number is contained in another number division to break up a number into equal parts dollar a unit of money double twice as many doubles numbers added to themselves, such as 2 + 2 = 4; 4 + 4 = 8; 8 + 8 = 16 E edge the straight side of a 2D object; where two faces of a 3D shape meet equal(s) the same as, shown by the sign = equivalent the same as something else estimate a sensible guess, or to make a sensible guess even the same in size; even numbers are all numbers ending in 0, 2, 4, 6 or 8 F face surface of a solid shape fifty the number 50 first, second, third, … ordinal numbers, written as 1st, 2nd, 3rd … fives used when counting 5 numbers on or back, for example, 5, 10, 15, 20 forty the number 40 1 fraction a part of something or part of a number, for example, 4 G gram (g) there are 1000 grams in one kilogram group to gather/collect H half something divided by 2 half turn not a full turn; half of it halve to divide something by 2 heaviest weighs the most; has the most mass 197 9781398300941_HCP_MATH_S2_LB.indb 197 2021/05/28 15:58 Mathematical dictionary hour a unit of time hour (60 minutes) hour hand the shorter arrow on an analogue clock; points to the hour hundred the number 100 I inverse opposite; subtraction is inverse to addition; multiplication is inverse to division K kilogram (kg) a measurement of weight (equal to 1000 grams) 0g 500 g 1000 g L length how far from one point to another less not as many lightest weighs the least; has the least mass likely a good chance of something happening line of symmetry a line line of symmetry that divides something into two identical halves litre a unit of measurement (equal to 1000 millilitres) M mass how much something weighs measuring cylinder a container to measure liquids measuring scale marks or lines on a measuring instrument to show the value, for example, grams, millilitres or litres; similar to a continuous number line where in-between marks have values metre (m) a unit of length (equal to 100 cm) might happen used in chance; will possibly happen millilitre there are 1000 millilitres in one litre minute there are 60 minutes in 1 hour; there are 60 seconds in 1 minute minute hand the longer arrow on an analogue clock; points to the minutes month there are 12 months in a year: January, February, March, April, May, June, July, August, September, October, November, December more greater in number or size multiple of 10 a number that can be divided equally by 10 multiplication an operation that we can represent as repeated addition or as an array N note(s) paper money numeral a figure or symbol that stands for a number O odd all numbers ending in 1, 3, 5, 7 or 9 one quarter one part of something divided into 4 parts ones shows the ones place value; numbers up to 9: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 198 9781398300941_HCP_MATH_S2_LB.indb 198 2021/05/28 15:58 Mathematical dictionary order an arrangement of objects or numbers from smallest to largest or largest to smallest P part-part-whole model when a whole is broken up into 2 or more parts, such as: 2 (part) + 13 (part) = 15 (whole) 15 2 15 13 2 13 pattern a repeated design on fabric or in numbers pictogram a picture that represents a word or a number popular well liked Q quarters something divided into 4 quarter turn a right-angle turn R regroup exchange for something with the same value, for example: regroup 10 ones to make 1 ten repeated addition to add over and over again, for example, 2 + 2 + 2 repeated subtraction to subtract over and over again, usually until you reach 0, such as 20 – 5 – 5 – 5 – 5 = 0 round done to find the nearest whole number; we can round 28 to 30; 21 to 20, 39 to 40 9781398300941_HCP_MATH_S2_LB.indb 199 S second comes after first seconds a minute has 60 seconds; a second is one sixtieth of a minute sequence the order in which something is arranged, such as numbers or events share to divide something between others side a line of a shape subtract to take away something from another subtraction a way of finding the difference between two numbers or things symmetrical each half is exactly the same This beetle is symmetrical. T tally a way of keeping a score or amount llll llll llll tally chart a chart used to keep a tally score tens shows the tens place value third comes after second and before fourth thirty the number 30 three quarters 3 of 4 parts __ 3 is shaded of something 4 times table a table showing numbers multiplied together total the answer to an addition calculation turn to rotate or change position twenty the number 20 two quarters half of __ 12 is shaded something 199 2021/05/28 15:58 Mathematical dictionary twos the numbers used when counting, for example, 2, 4, 6, 8 … or 11, 13, 15, 17, 19 V Venn diagram a diagram with circles to show sets Even numbers 2 6 Multiples of 5 10 20 12 14 5 25 15 Thinking and Working Mathematically (TWM) skills vocabulary characterising identifying and describing the mathematical properties of an object classifying organising objects into groups according to their mathematical properties conjecturing forming mathematical questions or ideas 35 W week there are 7 days in a week: Monday, Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday whole turn whole turn a full rotation will happen used in chance; something that is certain to happen will not happen used in chance; something that is certain not to happen Y year 365 (or 366) days make a year convincing presenting evidence to justify or challenge a mathematical idea or solution critiquing comparing and evaluating mathematical ideas, representations or solutions to identify advantages and disadvantages generalising recognising an underlying pattern by identifying many examples that satisfy the same mathematical criteria improving refining mathematical ideas or representations to develop a more effective approach or solution specialising choosing an example and checking to see if it satisfies or does not satisfy specific mathematical criteria This calendar shows the 12 months of a year. 200 9781398300941_HCP_MATH_S2_LB.indb 200 2021/05/28 15:58 Cambridge Primary Mathematics Teacher’s Guide with Boost Subscription Created with teachers and students in schools across the globe, Boost is the next generation in digital learning for schools, bringing quality content and new technology together in one interactive website. The Cambridge Primary Mathematics Teacher’s Guides include a print handbook and a subscription to Boost, where you will find a range of online resources to support your teaching. ● Confidently deliver the revised curriculum framework (0096): Expert author guidance and explanations for new mathematical content, an introduction on the mastery approach and emphasis throughout on thinking and working mathematically. ● Develop key concepts and skills: Let learners see how their skills are developing with a range of activities, assessment ideas, success measures and knowledge tests for stages 5 and 6. ● Support the use of ESL: Introductions and activities included that have been developed by an ESL specialist to help facilitate the most effective teaching in classrooms with mixed English abilities. ● Enrich learning: Character artwork taken from the Learner’s Books to be used front of class, audio recordings of the vocabulary in the Learner’s Books and flashcards with pictures and words based on the vocabulary covered. To purchase Cambridge Primary Mathematics Teacher’s Guide with Boost Subscription, visit www.hoddereducation.com/cambridgeprimary-maths