Step 4 Objective
Extend written methods to column addition and subtraction of numbers involving decimals.
- Examples of what pupils should
know and be able to do - Probing questions
- What if pupils find
this a barrier?
Probing questions
Make up an example of an addition/subtraction involving decimals that you would do in your head and one you would do on paper. Explain why.
Give pupils some completed questions to mark. All questions need to be written horizontally as well as in column form. Include incorrect answers such as 12.3 + 9.8 = 21.11; 4.07 − 1.5 = 3.92; 3.2 − 1.18 = 2.18. Which are correct/incorrect? How do you know? Explain what has been done wrong and correct the answers.