# Maths Year 4 Summer Multiplication and Division

Each unit has everything you need to teach a set of related skills and concepts.

## Factors, multiples, mental multiplication(suggested as 2 days)

### Planning and Activities

Day 1 Teaching
Children list the pairs of factors of 20. Write 20 × 36 on the board. Agree that we can solve this by multiplying 36 by 2, then by 10 (or vice versa). Explain that when we do this we are using the factors of 20. Encourage children to reflect on their preferences: Which way did you find quicker or made more sense? Children list the pairs of factors for 14, then use factors to work out 14 × 52. Repeat for 24 × 45.
Group Activities
Use the ‘Race to 200’ in-depth problem-solving investigation below as today’s group activity.
Or, use these activities:
-- Children multiply 23 by 8, 12, 14, 16 and 18 by listing factors and using a chosen pair to aid multiplication.
-- Use a ‘broken’ calculator to multiply 379 by 6, 8, 12, 18 and 24 by listing factors and using a chosen pair to aid multiplication.

Day 2 Teaching
Write 2 + 7 + 8 and ask children how they would work this out. Draw out changing the order to add the pair to 10, then add 7. Say that multiplication can also be done in any order. Write 4 × 7 × 5. How could we change the order of this multiplication that might simplify the calculation? Model reordering as 4 × 5 × 7, i.e. working out 20 × 7. Repeat with 7 × 2 × 8.
Group Activities
-- Children multiply three numbers 2-9, recognising where reordering can simplify the calculation. Record the multiplication in order in books; write a sentence to explain choice.
-- Children multiply three numbers, recognising where factors and reordering can simplify the calculation. Record the multiplication in order in books; write a sentence to explain choice.

### You Will Need

• Calculators
• Mini-whiteboards and pens
• Number cards 2–9
• Flipchart and pens

### Mental/Oral Maths Starters

Day 1
7 times table (pre-requisite skills)

Day 2
11 times table (pre-requisite skills)

### Worksheets

Day 1
List factors, then choose a pair to help work out multiplications.

Day 2
Choose a number from each star. Decide the easiest order to multiply them together.

### Mastery: Reasoning and Problem-Solving

• Find three different multiplication facts that you can multiply by 10 to give an answer of 400.
23 x 4 18 x 8 141 x 4
• How could you use the factors of 12 to help multiply a number by 12?
Try this to find:
16 x 12 23 x 12 34 x 12
• Use and explain a mental method to find:
8 x 13 7 x 16 12 x 13

In-depth Investigation: Race to 200
Children apply knowledge of factors within the 2, 3, 4, 5, 9 and 10x tables.

### Extra Support

Creepy Crawlies
Learning the 6 times table

Sleeping Spiders
Learning the 8 times table