Maths Calculation Policy This policy sets out the progression for maths calculation within Newchurch Primary School Each stage follows the logical next steps in mathematical understanding and offers help and guidance to support your child. Once children become secure with one method they will be encouraged to move on to the next stage. Addition Subtraction Multiplication Division Addition No formal written notation will be used until Stage 3 Stage Method Objective and vocabulary • Counting to find the total number of objects. • Setting out neatly to avoid double counting. • Conservation of number (same number even when set out in a different pattern). Counting sets of objects 1 = 3 count, number, total What can you do at home? also = 3 • Count objects at home (How many teddies are there on your bed? How many flowers?) • Remember to mix objects. How many toys on the floor? Addition Stage 2 Method Combining two sets of objects into one group to find the total. + = Extend to numbers up to 20 using multilink/cubes. Children will be asked to find one group of 5 cubes and then one group of 9 cubes and then combine to find the total. Objective and vocabulary • To be able to add groups to a total of 9. • To be able to add groups to a total of 20. Add, total, group, altogether What can you do at home? • Add different coloured toys or different coloured pencils/pens. • How many blue cars/pencils? How many red cars/pencils? How many altogether? Addition Stage Method Objective and vocabulary Drawing pictures/dots – informal jottings. 3 Then counting the total. **** + ***** = ********* Extend to using numbers to represent the jottings. 4 + 5 = 9 • To be able to count a series of objects and represent them with abstract jottings (dots, lines etc) and then find the total. • To use numbers (symbols) to represent the dots. symbol, represents, equals What can you do at home? • Count objects at home and record results using jottings (dots or marks). • Encourage setting out correctly. • Extend to represent the jottings with numbers. Addition Stage Method Counting on, on a number line (with numbers) 4 4 more than 3 is 7 Objective and vocabulary To be able to count on from the highest number in the calculation (3 + 6 - hold 6 in their head and count/jump on 3). • To count on one ’jump’ at a time to check understanding of number system. • number line, count on, more than What can you do at home? • Encourage your child to make or draw their own number line. Addition Stage Method Objective and vocabulary Use number lines to record steps in a calculation. 5 • To carry out an addition calculation (TU + U) using an empty number line (one which holds less This extension of Stage 4 will help children to add information – using the higher number at the beyond ten. Steps will then bridge through multiples beginning of the number line). of ten. • To use partitioning in a TU + TU calculation 16 + 7 = 23 (7 is broken down into 4 and 3) 1. Partition the lower number into ten and units (place value should be secure at this stage e.g. 36 is 3 tens and 6 ones). 2. Add the tens to you calculation. 3. Add the ones to your calculation. Moving on to partitioning TU + TU: 47 + 35 = 82 47 + 30 + 5 steps, jump, bridge, partition, tens, units What can you do at home? • Make/draw an extended number line • Give 2 digit numbers, e.g. 23 - How many tens? How many ones? Addition Stage 6 Method Continue to use partitioning without the use of a number line. 23 + 34 = 57 Objective and Vocabulary • To use written partition methods to support calculations (TU + TU, extending to HTU) partition, written method, columns What can you do at home? • Practise written method using partitioning. • Encourage children to take care that numbers are written neatly in the correct HTU columns. Addition Stage Method Written column method – continuing to use partitioning. Always starting using the column on the right. Objective and vocabulary • To use column addition with partitioning for numbers up to 1 decimal place. columns, hundreds, tens, ones/units, decimal (tenths) What can you do at home? 7 • Encourage children to take care that numbers are written neatly in the correct HTU.1/10 columns. Extend to decimals: 23.7 + 12.9 1.6 5.0 30.0 36.6 (0.7 + 0.9) Addition Stage Method Moving on to efficient written methods 8 Objective and vocabulary • To use an efficient written method for adding 2 and 3(or more) digit numbers including up to 2 decimal places. carry What can you do at home? Use and apply knowledge of decimals to adding money. • Give opportunities for adding money both mentally and using written methods • Reinforce 0.09 represents 9/100 = 9 pence whereas 0.9 represents 9/10 = 90/100 = 90 pence • Place value should be secure at this stage H T U . 1/10 1/100 (tenths/hundredths) Subtraction No formal written notation need be used until Stage 3 Stage Method Counting sets of objects 1 Objective and vocabulary • • • To be able to count sets of objects To recognise groups with fewer objects. Find the total number of objects in a group, remove some, and find the new total. count, number, take away, more, less, total What can you do at home? Take away 1 teddy which leaves: objects • • • Count objects at home (How many teddies are there on your bed? How many flowers? etc.) Remove one of the objects and recount. Remember to mix objects. How many toys on the floor? If I take one away, how many are there left? Subtraction Stage Method Objective and vocabulary Record calculations using drawings of objects. 2 6 - 3 = 3 • To be able to use drawings to represent calculations – moving on to numerical symbols. take away, subtract, less, symbol (6,-,=) What can you do at home? • Talk through calculation to aid understanding of method and vocabulary. • Draw pictures at first progressing onto symbols. Subtraction Stage 3 Method Counting back from a given number on a number line (with numbers). Objective and vocabulary • To count back, using the number line for support (discussing number of ‘jumps’ moved back). number line, backwards, forwards, count back, subtract, minus, less than, steps, jump What can you do at home? Use of multilink/dienes as reinforcement initially. 3 less than 7 = 4 • Make/draw a number line at home (highlighting each ten). Subtraction Stage Method Use number lines to record steps in a calculation. 4 This extension of Stage 3 will help children to subtract higher number. Steps will often mark a bridge through a multiple of 10. Objective and vocabulary To count differences by counting back (breaking down numbers into tens and ones where necessary). • To check calculation by using the inverse calculation or counting on. • 47 – 23 = 24 number line, count back, steps, jumps, bridge, tens, units/ones, difference, inverse Partition smaller numbers - 2 tens and 3 ones. What can you do at home? Encourage your child to make/draw their own number line. • Partition smaller numbers. • Encourage a wide range of vocabulary is used to describe calculations. • 82 – 35 = 47 47 count on to 82 Subtraction Stage 5 Method Objective and vocabulary Partitioning using symbols – writing numbers in groups below one another. 76 - 34 = 42 70 - 30 6 4 40 2 bridge, tens, units/ones, difference, inverse What can you do at home? Check using number line (counting on). Extend to larger numbers. 2543 - 1321 = 1222 - 2000 1000 1000 500 300 200 • To carry out calculations using partitioning (extending to larger numbers where no borrowing is required). 40 20 20 3 1 2 • Partition numbers. • Ensure column subtractions lined up correctly. • Ensure smaller number is subtracted from larger number. Subtraction Stage Method 72 – 47 = 25 6 Objective and vocabulary • To carry out calculations using partitioning where borrowing is used (ensure method is fully secure before introducing decomposition /borrowing). • Extend to larger numbers when secure. bridge, tens, units/ones, difference, inverse What can you do at home? • Practise written method using partitioning to check initially. • Ensure columns are lined up correctly and neatly Subtraction Stage 7 Method Continue to use partitioning until secure then move on to column subtraction 89 – 64 = 25 89 - 64 25 Extend to larger numbers Objective and vocabulary • To use efficient written methods to support calculations (TU - TU, extending to HTU). • To use efficient written methods. • Once column subtraction is secure, move on to using decomposition. partition, column, borrow across Stage Method Extend to decimals: 8 8.6 - 4.2 8.6 - 4.2 4.4 Objective and vocabulary • To use column subtraction using decimals up to two places. • Ensure columns are lined up correctly. columns, hundreds, tens, ones/units, decimal (tenths) (hundredths) Extend to 2 decimal places linking to money. £33.24 - £ 21.12 = £12.12 33.24 - 21.12 12.12 Decomposition can be used when secure. In a calculation giving change from whole £, it is more sensible to use the counting on number line method. What can you do at home? • Encourage children to take care that numbers are written neatly in the correct HTU.1/10 1/100 columns. • Give opportunities for handling money and giving change (encourage mental methods). Multiplication No formal written notation need be used until Stage 3 Stage 1 Method Counting groups of objects Objective and vocabulary • To be able to count groups of objects. count, number, groups What can you do at home? • Count a group of objects at home by breaking down into groups of 2, 3, 4 or 5. • Emphasis should be on counting and grouping rather than finding totals. Groups of 4 Multiplication Stage Method Breaking the total into groups. 2 12 = 3 lots of 4 Objective and vocabulary • To be able to multiple by breaking the total into groups. group, lots of What can you do at home? • Talk through calculation to aid understanding of method and vocabulary. • Use objects and manipulate into groups. Multiplication Stage Method Objective and vocabulary Set out calculations as arrays 3 ***** ***** ***** ***** **** **** **** **** **** 4x5 5x4 Both total 20 • To learn the relationship between a number and its factors. • To know the order of digits in a calculation does not make a difference to its total. array, times tables What can you do at home? • Arrange items into arrays. • Set arrays out neatly. • Count items and show that different patterns total the same. • Link to times tables. Multiplication Stage Method Multiplication as repeated addition. 4 Objective and vocabulary • Identify that 5 x 3 = 15 is the same as: To record multiplications and repeated additions in formal notation 5x3=3+3+3+3+3 lots of, groups of, times, repeated addition What can you do at home? Encourage your child to make/draw their own number line. • Count up to a total by grouping/jumping in 2, 3, 4, 5 etc. • Use a number line to aid understanding Multiplication Stage Method Partitioning into composite parts 5 13 x 5 (10 x 5) + (3 x 5) 50 + 15 = 65 Objective and vocabulary • To multiply by partitioning. • To calculate brackets first. partition, brackets, tens, units What can you do at home? Pupils will know method for multiplying by 10 by moving digits to left and using zero as place holder. • Practise calculations by partitioning numbers and showing brackets. • Ensure children use knowledge of place value to x 10 etc. Multiplication Stage 6 Method Objective and vocabulary Continue to use partitioning to multiply using grid method. • To use the grid method for multiplying TU x U then extend to TU X TU and HTU X TU. 23 x 8 = 184 160 + 24 184 63 x 24 x 60 3 20 1200 60 4 240 12 1440 + 72 = 1512 What can you do at home? • Practise using the grid method for TU x U until secure. • Encourage your child to recognise that 20 x 30 is (2 x 10) x (3 x 10) and the calculation is 2 x 3 x 10 x 10 so there would be 2 zeros in the answer 600. Multiplication Stage 7 Method TU X U showing calculations and multiplying by the units first. 39 X 7 63 210 273 (7 x 9) (7 x 30) Extend to short multiplication TU X U. Objective and vocabulary • To use short multiplication for TU X U and including decimals. • Ensure columns are lined up correctly especially the decimal point. tens, units, carry What can you do at home? • Encourage children to take care that numbers are written neatly in the correct H T U.1/10 1 /100 columns. Multiplication Stage Method TU x TU long multiplication for some children. 8 Use grid method alongside initially to show calculation link. 63 X 24 12 240 60 1200 1512 Objective and vocabulary • To use the long multiplication method when x TU. • Refer to number of zeros. What can you do at home? (4 x 3) (4 x 60) (20 x 3) (20 x 60) • Encourage children to take care that numbers are written neatly in the correct H T U columns. • Encourage checking using the grid method initially. Division No formal written notation need be used until Stage 3. Stage Method Sharing Objective and vocabulary • To be able to share objects share 1 What can you do at home? • Share objects at home between family members. Share the apples between the teddies. How many each? Division Stage Method Objective and vocabulary Sharing/grouping - breaking the total into groups. 2 • To be able to share by breaking the total into groups. share, group, divide, fair, equal What can you do at home? 12 ÷ 4 = 3 12 apples 3 teddies • Talk through calculation to aid understanding of method and vocabulary. • Use objects and manipulate into groups. Division Stage Method Recognise grouping as repeated subtraction. 3 Objective and vocabulary • To be able to share and group using a number line. share, share equally, group, lots of divide, divided by, divided into, division, grouping, number line, left, left over What can you do at home? • Encourage your child to make/draw a number line. Division Stage Method Short division with no remainders. 4 Objective and vocabulary • To use short division to divide TU by U with no remainders. Show partition. 84 ÷ 2 = 42 (80 4) ÷ 2 = (40 2) short division, partition, place value, divide, bus-stop method, inverse What can you do at home? • Talk through calculation to aid understanding of method and vocabulary. • Reminder of place value. • Encourage checking using inverse. Remind children of correct place value: How many 2s in 8? Record above the 8 tens. How many 2s in 4? Record above the 4 units. Division Stage 5 Method Short division with remainders once Stage 4 is secure. Objective and vocabulary • To use short division TU by U with remainders. Short division, partition, place value, divide, bus-stop method, inverse, remainder What can you do at home? Continue to develop with decimal numbers. • Talk through calculation to aid understanding of method and vocabulary. • Reminder of place value. • Encourage checking using inverse until secure. Division Stage 6 Method Division using the chunking method. Remind children division is repeated subtraction. Objective and vocabulary • To divide HTU by TU. division, divide, chunk, repeated subtraction, groups of, halving, doubling, multiples of 10 What can you do at home? • Talk through calculation to aid understanding of method and vocabulary. • Encourage checking using inverse until secure. • Once secure, encourage children to subtract the highest amount possible by finding 10x the divisor, then doubling to find 20x and so on. Division Stage 7 Method Once secure with chunking, introduce long division alongside Stage 6. Objective and vocabulary • To divide by a single digit using long division. • To divide by 2 digits using long division. Introduce initially by a single digit then move on to dividing by 2 digits. What can you do at home? • Talk through calculation to aid understanding of method and vocabulary. • Encourage checking using inverse until secure.