Step 3 Objective

Extend efficient written methods to short multiplication of HTU or UT by U.

Examples of what pupils should know and be able to do

Use the grid method, e.g.
346 × 9 is approximately 350 × 10 = 3500

346 times 9 = (300 times 9) + (40 times 9) + (6 times 9)

Use partitioning, e.g.
346 × 9 is approximately 350 × 10 = 3500

346 times 9 = (300 times 9) plus (40 times 9) plus (6 times 9) = 3114

Probing questions

Talk me through your method. What two numbers have you multiplied together to get this part of the answer?

Give pupils some worked examples that are incorrect. Is this correct? How do you know? What do you need to do to put it right?

What if pupils find this a barrier?

Use the grid method for both HTU × U and TU × U as this builds on pupils' mental strategies. Encourage pupils to say the numbers to keep a sense of the place value. Develop towards the partitioning method, making sure pupils can see the links with the grid.

For guidance on written multiplication refer to the document 'The National Numeracy Strategy: Teaching written calculations – guidance for teachers at Key Stages 1 and 2' (QCA/99/486) pp. 49 – 55.