1. Multiplication and Division Double and halve 2- and 3-digit numbers
Objectives
Day 1
Double and halve 2-digit numbers, including odd numbers.
Day 2
Double and halve 3-digit numbers.
Before teaching, be aware that:
On each day children will need whiteboards and pens.
You may want to use a set of Place Value cards to model the partitioning of 2- and 3-digit numbers.
Year 4

2. Multiplication and Division Double and halve 2- and 3-digit numbers
Starters
Day 1 Double the numbers 1 to 20 and find the corresponding halves (pre- requisite skills)
Day 2 Double and halve multiples of 100 (pre-requisite 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

3. Multiplication and Division
Double and halve 2- and 3-digit numbers
Starter Double the numbers 1 to 20 and find the corresponding halves
Top Marks doubles and halves
Pre-requisite skills – to use this starter, drag this slide to the start of Day 1
Revise doubles to 20 and corresponding halves. Then play Top Marks doubles and halves at choosing Half (20) and clicking to reveal some numbers in the pink zones and some in the green. Ideally, children play individually on mobile devices, or write answers on whiteboards as you point to the empty spaces.
Year 4

4. Multiplication and Division
Double and halve 2- and 3-digit numbers
Starter Double and halve multiples of 100
Pre-requisite skills – to use this starter, drag this slide to the start of Day 2
Ask children to show you on their whiteboards double 100, double 200 … until you have doubled all multiples of 100 to Agree each answer and generate a reminder sheet on a flipchart: double 100 is 200, etc. Repeat, this time halving multiples of 100. Discuss how when the 100s digit is odd, the calculation is a little trickier and there will be a 50 in the answer. As you discuss each halving, record it on the flipchart: half 100 is 50, etc.
Year 4

5. Multiplication and Division Double and halve 2- and 3-digit numbers
Objectives
Day 1
Double and halve 2-digit numbers, including odd numbers.
Year 4

6. We can partition 26 into 10s and 1s. and double each part.
Day 1: Double and halve 2-digit numbers, including odd numbers.
Let’s double 26.
We can partition 26 into 10s and 1s. and double each part.
Double 26
Double 20 is ? 40 12
= 52
Double 6 is ?
= ?
Now choose three more 2-digt numbers and double them.
Can you find one that totals more than 100?
Year 4

7. Let’s try 75. Double 75 Double 70 is ? Double 5 is ? 140
Day 1: Double and halve 2-digit numbers, including odd numbers.
Let’s try 75.
Double 75
Double 70 is ?
Double 5 is ?
140 10
= 150
Double 75 is ?
Now 84.
Double 84
Double 80 is ?
160 8
Double 4 is ?
= 168
Double 84 is ?
Year 4

8. Now on your whiteboards find half of 34 and half of 96.
Day 1: Double and halve 2-digit numbers, including odd numbers.
Now let’s find half of 26.
Half of 26
Half of 20 is ? 10 3
= 13
Half of 6 is ?
Half of 26 is ?
Now on your whiteboards find half of 34 and half of 96.
What makes those a bit trickier?
Year 4

9. What do you notice about the 10s in those two questions?
Day 1: Double and halve 2-digit numbers, including odd numbers.
Let’s check those.
Half of 34
Half of 96 15 2 45 3
= 17
= 48
What do you notice about the 10s in those two questions?
Year 4

10. Now let’s see what happens when the 1s digit is odd.
Day 1: Double and halve 2-digit numbers, including odd numbers.
Now let’s see what happens when the 1s digit is odd.
Half of 23 10
11/2
/2 = 111/2
How can you halve the odd 1s digit?
Now on your whiteboards find half of 47 and half of 59.
Year 4

11. Who can talk us through this one?
Day 1: Double and halve 2-digit numbers, including odd numbers.
Let’s check those.
Half of 47
Half of 59 20
31/2 25
41/2
/2 = 231/2
/2 = 291/2
Today would be a great day to use a problem-solving investigation – Doubling Forever – as the group activity, which you can find in this unit’s IN-DEPTH INVESTIGATION box on Hamilton’s website.
Alternatively, 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: Double and half selected 2-digit numbers, with support.
ARE: Doubling and halving 2-digit numbers (randomly generated).
GD: Doubling and halving 2-digit numbers (more odd digits).
Who can talk us through this one?
And this one?
Year 4

12. 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: Doubles and Halves Sheet 1.
ARE: Doubles and Halves Sheet 2.
GD: Doubles and Halves Sheet 3. .
Challenge
Year 4

13. Multiplication and Division Double and halve 2- and 3-digit numbers
Objectives
Day 2
Double and halve 3-digit numbers.
Year 4

14. Let’s check through the doubles of 100s numbers. 200 400
Day 2: Double and halve 3-digit numbers.
100
200
Let’s check through the doubles of 100s numbers.
200
400
300
600
400
800
500
1000
We can use these to help us double 3-digit numbers!
600
1200
700
1400
800
1600
900
1800
1000
2000
Year 4

15. Now on your whiteboards find double 471 and double 638.
Day 2: Double and halve 3-digit numbers.
Let’s try double 226.
Double 226
Partition into 100s, 10s and 1s.
400 40 12
= 452
Double 200 is ?
Double 20 is ?
Now on your whiteboards find double 471 and double 638.
Double 6 is ?
Three numbers to add this time!
Year 4

16. Who can talk us through this one? Careful with the addition!
Day 2: Double and halve 3-digit numbers.
Double 471
Who can talk us through this one?
800
140 2
= 942
Double 638
And this one?
Careful with the addition!
1200 60 16
= 1276
Year 4

17. 3-digit numbers in the same way.
Day 2: Double and halve 3-digit numbers.
We can find HALF of
3-digit numbers in the same way.
Half 226
100 10 3
Half of 200 is ?
= 113
Half of 20 is ?
Half of 6 is ?
Now on your whiteboards find half of 326, 452 and 643.
Half of 226 is ?
Be careful with any odd digits!
Year 4

18. Let’s check. Who can talk these through?
Day 2: Double and halve 3-digit numbers.
Let’s check. Who can talk these through?
Half 326
Half 452
Half 643
150 10 3
200 25 1
300 20
11/2
= 163
= 226
/2 = 3211/2
The 100s digit in 362 is odd.
The 10s digit in 452 is odd.
The 1s digit in 643 is odd.
Year 4

19. Let’s work together to find half of 531.
Day 2: Double and halve 3-digit numbers.
Let’s work together to find half of 531.
Half 531
250 15
1/2
What do you notice about the digits in 531?
/2 = 2651/2
Half of 500 is ?
Half of 30 is ?
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: Halving 3-digit numbers on place value board.
ARE/GD: : Halving 3-digit numbers and checking by doubling.
Half of 1 is ?
Half of 531 is ?
Year 4

20. 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: Start at Section A.
ARE: Section B and then do as many of Section C as they can.
GD: Every other question of Sections A and B, then work through Section C.. .
Challenge
Year 4

21. Multiplication and Division Double and halve 2- and 3-digit numbers
Well Done! You’ve completed this unit.
Objectives
Day 1
Double and halve 2-digit numbers, including odd numbers.
Day 2
Double and halve 3-digit numbers.
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

22. Multiplication and Division Unit 1
Problem solving and reasoning questions
Write two sentences to relate these three numbers: 37, 74 and 148.
Use a jotting to double these numbers:
(a) 216
(b) 327
(c) 438
Can you describe a pattern in the answers?
We know double 30 is 60 and double 8 is 16.
So what is half of 76?
Explain in a sentence why a jotting is helpful when we find half of 318.
Year 4