Short Blocks

# Maths Year 3/4 Summer Multiplication and Division (B)

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

## Partitioning to double, halve and multiply(suggested as 3 days)

### Planning and Activities

Day 1
Use place value cards as a supporting model to revise doubling and halving 2-digit numbers by partitioning and recombining.
Group Activities: T with Y3
Y3/4 Whole class -- Play a ‘chain’ game, halve numbers if even; add 1 when numbers are odd.
Y3 -- Play a 4-in-a-row grid game, doubling 2-digit numbers.
Y4 Use the in-depth problem-solving investigation ‘Set Square’ as today’s group activity.
Or, use this activity:
-- Play a 4-in-a-row grid game, halving 2-digit numbers.

Day 2
Model the grid method for multiplying 2-digit by 1-digit numbers: 14 × 2, 14 × 3, 14 × 6.
Further Teaching with Y4
Model the ladder method and compare to the grid method for 3-digit by 1-digit multiplication, e.g. 786 × 4.
Group Activities: T with Y3
Y3 Use the in-depth problem-solving investigation ‘18 Times Table – Wow!’ as today’s group activity.
Or, use these activities:
-- Describe stepping stones in developing use of the grid method. Rehearse use of preferred image(s) to begin using the grid method.
-- Practise multiplying smaller 2-digit numbers by 1-digit numbers.
Y4 -- Solve 3-digit by 1-digit multiplication challenges.

Day 3
Further shared learning of the grid method to build the 24 times table from 1 × 24 to 10 × 24. Link repeated addition to multiplication.
Further Teaching with Y4
Estimate and solve multiplications: 4 × 782 618 × 6 5 × 579.
Group Activities: T with Y4
Y3 -- Investigate multiplying odd and even 2-digit numbers by 1-digit numbers using the grid method.
Y4 -- Use a written method for 3-digit by 1-digit multiplications, finding answers in a number of given ranges.

### You Will Need

• ITP Place Value
• Mini-whiteboards and pens
• ‘Doubling numbers’ Sheets 1 and 2 (see resources)
• Coloured pencils
• Sets of 100s, 10s and 1s place value cards
• ‘Halving numbers’ Sheets 1 and 2 (see resources)
• ‘Steps towards using the grid method for 14 × 5’ Sheets 1 and 2 (see resources)
• ‘Using the grid method’ (see resources)
• Flipchart and pens
• Squared paper
• Number cards 1–9, 11–30 and 21–40

### Short Mental Workouts

Day 1
Times tables bingo

Day 2
30 times table

Day 3
Multiply and divide by 10 and 100

### Worksheets

Day 1
Y3 Double and halve 2-digit numbers.
Y4 Halve 2 and 3-digit numbers.

Day 2
Y3 Grid multiplication.
Y4 Written multiplication.

Day 3
Y3 Grid multiplication.
Y4 Written multiplication.

### Mastery: Reasoning and Problem-Solving

Y3

• How many odd numbers between 50 and 100, when halved, give an answer ending 4¹/2?
• Now complete the addition to find the total of the partial products:
☐ + ☐ = ☐

Y4

• Calculate: 154 × 7; 6 × 289; 4 × 5 × 9 × 3
• This calculation has the same number missing from each box. Write the missing number in the boxes. ☐ × ☐ – ☐ = 72
• A shop sells some boxes of ‘Triple-Chocs’ that cost £3.58 each, and makes £32.22. How many boxes did they sell?

Y3 In-depth Investigation: 18 Times Table – Wow!
Children use the grid method to derive the 18 times table, then look for patterns in the answers.

Y4 In-depth Investigation: Set Square
Use digits 1–9 once only to complete a calculation grid with given answers for each row and column.

### Extra Support

Y3: Doubles Decisions
Doubling numbers up to 50.

Harder Halves
Halving even numbers to 100.

Y4: Multiplication Mix
Using the grid method to multiply 2-digit numbers by 1-digit numbers.