Mathematics Alignment Lesson Grade 5 Quarter 1 Day 15 Common Core State Standard(s) 5.NBT.3 Read, write, and compare decimals to thousandths. a. Read and write decimals to thousandths using base-ten numerals, number names, and expanded form, e.g., 347.392 = 3 x 100 + 4 x 10 + 7 x 1 + 3 x (1/10) + 9 x (1/100) + 2 x (1/1000) b. Compare two decimals to thousandths based on meanings of the digits in each place, using >, =, and < symbols to record the results of comparisons. Standards for Mathematical Practice Standard 7 – Look for and make use of structure. Materials Needed: Base Ten Blocks for each student (flats, rods, units) Blackline Masters, “Blank Base Ten Grids A,” “Blank Base Ten Grids B,” Transparency/Blackline Master“Base Ten Grids” Assessment Informal: Circulate to check for understanding during partner and independent practice times. “Blank Base Ten Grids A and B” and “Decimal Place Value Practice Homework Blackline Master- “Decimal Place Value Practice” Vocabulary Thousandth: one part out of 1,000 equal parts of a whole; the position of the third digit to the right of the decimal point Wake County Public School System, 2012 Alignment Lesson Decimal Place Value with Base Ten Blocks and Grids 1. Distribute base ten blocks to each student and instruct them to use rods to cover a flat. Discuss “Question Set A” on Teacher Guide, “Decimal Place Value Discussion Questions.” 2. Engage the class in a discussion about the corresponding decimal notations from questions 2–4 (0.1, 0.7, and 0.4) and the relationship between fractions and decimals. Then, discuss “Question Set B” on Teacher Guide, “Decimal Place Value Discussion Questions.” 3. Ask students to write the number that represents 3 flats, 5 rods, and 7 units using decimal notation. (3.57) 4. Ask students to arrange their base ten blocks to show 2.34. (2 flats, 3 rods, 4 units) 5. Engage students in several more whole class examples, similar to the ones in steps 3 and 4, to check for understanding. Then, invite student pairs to ask each other similar types of questions to practice. 6. Display Transparency/Blackline Master, “Base Ten Grids” and present Grid A. Discuss “Question Set C” on Teacher Guide, “Decimal Place Value Discussion Questions.” 7. Distribute Blackline Master, “Blank Base Ten Grids A,” and write several numbers on the board for students to shade, including numbers less than 1, numbers between 1 and 2, and numbers greater than 2. Circulate to check for understanding and assist individual students, referencing the base ten blocks for students needing more concrete practice. 8. Display Transparency/Blackline Master, “Base Ten Grids” and present Grid B. Discuss “Question Set D” on Teacher Guide, “Decimal Place Value Discussion Questions.” 9. Distribute Blackline Master, “Blank Base Ten Grids B,” and write several numbers on the board for students to shade, including numbers less than 1, numbers between 1 and 2, and numbers greater than 2. Circulate to check for understanding and assist individual students. 10. Students should complete “Decimal Place Value Practice” for homework. Note: There are a large number of discussion questions in today’s lesson. To actively engage all students in continual thinking during the lesson, you may wish to have students turn and talk with established partners and then choose one person to share with the class for some of the “Decimal Place Value Discussion Questions.” Source: Teacher Created Teacher Guide Grade 5 Day 15 Standard 5.NBT.3 Decimal Place Value Discussion Questions Question Set A: 1. 2. 3. 4. How many rods did you use to cover the flat? 10 If a flat represents 1 whole, then what fraction does one rod represent? 1/10 What fraction of the flat is 7 rods? 7/10 What fraction of the flat is 4 rods? 4/10 Question Set B: 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. What decimal number is represented by 10 rods? 1.0 What decimal number is represented by 1 flat and 5 rods? 1.5 How many tenths are in two wholes? 20 How would you write 20 tenths using decimal notation? 2.0 How many small squares are in a flat? 100 Which base ten piece would you use to show one hundredth? unit Why? 100 units are in a flat, so one unit represents 1/100 of a flat How many hundredths does a rod represent? 10 How would you write 10 hundredths using decimal notation? 0.10 Do 0.10 and 0.1 represent the same number? yes Explain why 0.10 and 0.1 represent the same number using the base ten blocks. 0.10 represents 10 units and 0.1 represents 1 rod. Since 1 rod is equal to 10 units, 0.10 and 0.1 represent the same number. Question Set C: 16. 17. 18. 19. 20. How many small squares are on this grid? 100 What fraction of the grid does each small square represent? 1/100 What is the decimal representation for each small square? 0.01 What is the decimal representation for each row or each column? 0.10 or 0.1 If I shade 2 columns and 4 small squares, what decimal have I represented? 0.24 (Shade as you ask the question to aid student understanding.) Question Set D: 21. How many tiny rectangles are on this grid? 1,000 (You may wish to break each piece 22. 23. 24. 25. down to aid understanding… in each small square there are 10 tiny rectangles, and in each row of small squares, there are 100 tiny rectangles, so in 10 rows, there are 1,000 tiny rectangles) What fraction of the grid does each tiny rectangle represent? 1/1000 How do you think we might represent this number using decimal notation? 0.001 What do you think this place value is called? a thousandth Why? It represents a tenth of one hundredth or 1/1000 of a whole. If I shade 2 rows, 8 small squares, and 9 tiny rectangles, what decimal have I represented? 0.289 (Shade as you ask the question to aid student understanding.) Wake County Public School System, 2012 Transparency/Blackline Master Grade 5 Day 15 Base Ten Grids Grid A Grid B Wake County Public School System, 2012 Standard 5.NBT.3 Blackline Master Grade 5 Day 15 Standard 5.NBT.3 Name: ________________________ Date: ________________________ Blank Base Ten Grids A Wake County Public School System, 2012 Blackline Master Grade 5 Day 15 Standard 5.NBT.3 Name: ________________________ Date: ________________________ Blank Base Ten Grids B Wake County Public School System, 2012 Blackline Master Grade 5 Day 15 Standard 5.NBT.3 Name: ________________________ Date: ________________________ Decimal Place Value Practice 1. What number is represented by 3 flats, 7 rods, and 9 units? Write your answer in decimal notation. 2. What number is represented by 8 units, 1 flat, and 6 rods? Write your answer in decimal notation. 3. Shade 2.793 on the grids below. 4. Explain why 0.3, 0.30, and 0.300 are equivalent. Include base ten blocks or grids in your description. 5. Explain the relationship between thousandths and hundredths. Wake County Public School System, 2012 Answer Key Grade 5 Day 15 Standard 5.NBT.3 Decimal Place Value Practice Answer Key 1. What number is represented by 3 flats, 7 rods, and 9 units? Write your answer in decimal notation. 3.79 2. What number is represented by 8 units, 1 flat, and 6 rods? Write your answer in decimal notation. 1.68 3. Shade 2.793 on the grids below. Students should have shaded 2 whole squares, 7 columns, 9 small squares, and 3 tiny rectangles. 4. Explain why 0.3, 0.30, and 0.300 are equivalent. Include base ten blocks or grids in your description. 0.3 is equal to 3 tenths of the flat or 3 rods. Each of the rods can be broken into 10 units making 30 hundredths of the flat. The units are represented by the small squares on the base ten grid, and each of the small squares can be divided into 10 tiny rectangles, making 300 thousandths of the whole. 5. Explain the relationship between thousandths and hundredths. There are 10 thousandths in one hundredth, so a thousandth is one tenth of a hundredth, making it one thousandth of the whole. Wake County Public School System, 2012