Addition and Subtraction Use column addition, including to add amounts of money Objectives Day 1 Add three 3-digit numbers using compact addition. Use rounding to approximate. Day 2 Use compact addition to add amounts of money. Before teaching, be aware that: On Day 1 children will need mini-whiteboards and pens. On Day 2 children will need mini-whiteboards and pens. You will need books with price labels: £4.79, £5.49, £5.25, £4.65, £4.29. Year 4

Addition and Subtraction Use column addition, including to add amounts of money Starters Day 1 Add 3 multiples of 10 (pre-requisite skills) Day 2 8 times table (simmering skills) Choose starters that suit your class by dragging and dropping the relevant slide or slides below to the start of the teaching for each day. Year 4

Addition and Subtraction Use column addition, including to add amounts of money Starter Add 3 multiples of 10 Pre-requisite skills – to use this starter, drag this slide to the start of Day 1 Use Spinners at http://www.topmarks.co.uk/Flash.aspx?f=Spinners. Choose 3 spinners BODMAS, and click to set each spinner to T0 (this generates multiples of 10). Click on the centre of each spinner to get them to spin. If this Flash resource does not work, use 3 rolls of a 10s place value dice or choose three 10s place value cards. Children find the total and write on whiteboards. Repeat lots of times, building up speed. What number facts/ relationships are you using? Year 4

Addition and Subtraction Use column addition, including to add amounts of money Starter 8 times table Simmering skills – to use this starter, drag this slide to the start of Day 2 Using the Number grid ITP, highlight multiples of 8. Together chant the 8 times table: one 8 is 8, two 8s are 16… twelve 8s are 96. Children chose 6 multiples to write on their whiteboards. Shuffle a pack of 0 to 12 number cards. Show 1. Children multiply by 8 and ring the answer on their whiteboards. Repeat. First child to ring all 6 of their numbers wins. Year 4

Addition and Subtraction Use column addition, including to add amounts of money Objectives Day 1 Add three 3-digit numbers using compact addition. Use rounding to approximate. Year 4

Estimate the answer to each addition. Day 1: Add three 3-digit numbers using compact addition; Use rounding to approximate. 426 + 257 + 582 275 + 446 + 385 Estimate the answer to each addition. Let’s use compact addition to find the exact answer to 426 + 257 + 582. 4 2 6 2 5 7 Now work out the exact answer to 275 + 446 + 385 Compare the answer with your estimate. + 5 8 2 Did children round to the nearest multiple of 100 or only look at the first digit? Point out how, in most cases, the numbers round up in these additions, so looking at the first digit only doesn’t give a very accurate estimate. 1 1 1 2 6 5 How does the answer compare with your estimate? Year 4

Which will have a total more than 1000? Day 1: Add three 3-digit numbers using compact addition; Use rounding to approximate. 726 + 457 + 582 Round to the nearest 100 to estimate the answer and then find the exact total. 327 + 178 + 635 425 + 217 + 334 Which will have a total more than 1000? How can you tell? Year 4

Whole class investigation Day 1: Add three 3-digit numbers using compact addition; Use rounding to approximate. Whole class investigation Work in pairs to use the digits 1 to 9 to make additions of three 3-digit numbers. You can only use each digit once in each addition. Aim to make the biggest total possible, the smallest total possible, and a total as close to 1500 as you can. Feedback how you went about finding the greatest and least totals, and then a total near 1500. Which pair was closest? How close were you? Alternatively, today’s GROUP ACTIVITY is a whole class investigation. You can find more details in the unit’s TEACHING AND GROUP ACTIVITIES download. WT: Children make additions of two 3-digit numbers using digits 1 to 6, find the greatest and smallest totals, then use digits 1 to 9 to make three 3-digit numbers with the smallest total possible and one as close to 1000 as they can. Year 4

The Practice Sheet on this slide is suitable for most children. Differentiated PRACTICE WORKSHEETS are available on Hamilton’s website in this unit’s PROCEDURAL FLUENCY box. WT: Add pairs of 3-digiti numbers (sheet 1). ARE/GD: Add three 3-digit numbers (sheet 2). Challenge Year 4

Addition and Subtraction Use column addition, including to add amounts of money Objectives Day 2 Use compact addition to add amounts of money. Year 4

Explain to your partner how this was done, talking through each stage. Day 2: Use compact addition to add amounts of money. Explain to your partner how this was done, talking through each stage. Can you see how the 5p and 6p were added to make 11p, a 1 written under the pennies and the one 10p written under the 10p column waiting to be added to the other 10ps? Then 50p, 70p and 10p were added to make £1.30, the 3 written under the 10ps and the £1 under the pounds to be added to the £3 and £2. Year 4

Work in pairs to find all possibilities. Day 2: Use compact addition to add amounts of money. Look at the price labels on the books. You’ve been given £10 to spend for your birthday; you like all of these books, which two can you buy? Any other pair? Work in pairs to find all possibilities. Show children books with price labels: £4.79, £5.49, £5.25, £4.65, £4.29. Children can now go on to do differentiated GROUP ACTIVITIES. You can find Hamilton’s group activities in this unit’s TEACHING AND GROUP ACTIVITIES download. WT: Add pairs of amounts of money using expanded and then compact addition. ARE: Choose the most efficient method to add pairs of 3-digit amounts (some money). GD: Apply compact addition skills to add trios of 3-digit amounts of money. Year 4

The Practice Sheet on this slide is suitable for most children. Differentiated PRACTICE WORKSHEETS are available on Hamilton’s website in this unit’s PROCEDURAL FLUENCY box. WT: Use expanded and compact addition to add amounts of money, estimate totals (sheet 1). ARE/GD: Estimate totals then add amounts of money using compact column addition (sheet 2). Year 4

Addition and Subtraction Use column addition, including to add amounts of money Well Done! You’ve completed this unit. Objectives Day 1 Add three 3-digit numbers using compact addition. Use rounding to approximate. Day 2 Use compact addition to add amounts of money. You can now use the Mastery: Reasoning and Problem-Solving questions to assess children’s success across this unit. Go to the next slide. Year 4

Problem solving and reasoning questions Write these two numbers in expanded form, i.e. as hundreds + tens + ones: • 475 • 205 Add them mentally; write the total. Complete these using column addition: i. 367 + 272 ii. 548 + 237 iii. 479 + 258 + 382 iv. £6.29 + £5.75 Write the missing numbers in this calculation: £10.64 = £4.8□ + £□.□7 Year 4

Problem solving and reasoning: Answers Write these two numbers in expanded form, i.e. as hundreds + tens + ones: • 475 400 + 70 + 5 (NOT 4 + 7 + 5) • 205 200 + 5 Add them mentally; write the total. 680 Complete these using column addition: i. 367 + 272 = 639 ii. 548 + 237 = 785 iii. 479 + 258 + 382 = 1119 £6.29 + £5.75 = £12.04 Errors may be due to a) children not setting questions out neatly in columns b) arithmetical mistakes in adding single digits or c) forgetting or misunderstanding digits moved between columns. Also check that children are estimating answers before doing the calculations. Write the missing numbers in this calculation: £10.64 = £4.87 + £5.77 Year 4