Short Blocks

Maths Year 4 Spring Multiplication and Division (B)

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

Multiply multiples of 10 and 100 (suggested as 3 days)

Planning and Activities

Day 1 Teaching
Use ITP ‘Number Dials’, select 3 as the central number. Children count round in 3s. If we know the 3 times table, we can work out the 30 times table! Have 30 as the central number and repeat. These numbers are 10 times as big. Repeat for 6 and 60, then 8 and 80. Repeat for the 900 times table. Then repeat for 4, 40, 400; 7, 70, 700.
Group Activities
-- Multiply multiples of 10 and 100 by a range of 1-digit numbers.

Day 2 Teaching
Write 3 × 5, 3 × 50 and 3 × 500 on the Interactive Whiteboard. Children answer each in pairs. Show how 3 × 50 is the same as 3 × 5 × 10. Then show how 3 × 500 is the same as 3 × 5 × 100. Children then work in groups of 3 to work out 2 × 9, 2 × 90, 2 × 900. They repeat for 4 × 8, 4 × 80, 4 × 800 and 7 × 3, 7 × 30, 7 × 300.
Can I write an inverse division number sentence, based on knowing that 40 x 6 = 240? Explore grouping 240 in 40s and 6s.
Group Activities
-- Write multiplication and division facts for big numbers derived from multiplication tables.

Day 3 Teaching
Show four incomplete tables facts: 7 × 5 =, 3 × 8 =, 6 × 7 =, 4 × 9 =. Explain that these can help us to solve related multiplications and divisions, e.g. 7 × 50 = 350. Show how children can write related ‘mega-facts’, e.g. 350 ÷ 7 = 50.
Group Activities
Use the in-depth problem-solving investigation ‘Multiples Grid’ from NRICH as today’s group activity.
Or, use this activity:
-- Write ‘mega multiplications’, and associated divisions, based on a 12 × 12 tables-grid.

You Will Need

  • ITP ‘Number Dials
  • 1s–1000s place value grid (see resources)
  • 0–9 dice
  • ‘Ladder of 10s’ (see resources)
  • ‘Ladder of 100s’ (see resources)
  • ‘Target numbers’ (see resources)
  • ‘Multiplication grid’ (see resources)

Mental/Oral Maths Starters

Day 1
Count in steps of 40 (pre-requisite skills)

Day 2
Count on and back in multiples of 10 and 100 (pre-requisite skills)

Suggested for Day 3
Convert cm to mm (simmering skills)

Worksheets

Day 1
Multiply 1-digit numbers by 10s and 100s.

Day 2
Apply tables knowledge to write multiplication facts for multiples of 10 and 100, e.g. 480, 2400, 2100, 540, etc.

Day 3
Multiply 10s and 100s by 1-digit numbers. Derive associated division facts.

Mastery: Reasoning and Problem-Solving

  • Write 360 ÷ ☐ = ☐ and then complete the sentence in at least four different ways.
  • Jimmy writes: 40 x 5 = 2000.
    Is he correct? What might he not understand yet?
  • Write three mega-facts to match 4 × 8 = 32. At least one must be a division fact.
  • Which four number sentences link these numbers: 5600, 8, 700?

In depth Investigation: Multiples Grid
What do the shaded numbers on a 100 square have in common? Children apply knowledge of tables facts and divisibility. Multiples Grid from nrich.maths.org.

Extra Support

Moving multiplications
Multiplying by 20, 30, 40 and 50 using times tables and place value