Step 2 Objective
Use known number facts and place value to add or subtract mentally, including any pair of two-digit whole numbers.
- Examples of what pupils should
know and be able to do - Probing questions
- What if pupils find
this a barrier?
What if pupils find this a barrier?
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Identify which mental strategies are causing difficulties and focus teaching on these.
Encourage pupils to explain their mental strategies for adding pairs of two-digit numbers. Hearing other strategies helps develop understanding and extend calculation skills.
Refer to Teaching mental calculation strategies to L5 - Acrobat pdf document (554Kb) pp. 15-30.