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Prompt Cards

These two group activities use mathematical reasoning - one is numerical, one geometric.

Consecutive Numbers

An investigation involving adding and subtracting sets of consecutive numbers. Lots to find out, lots to explore.

Exploring Wild & Wonderful Number Patterns

EWWNP means Exploring Wild and Wonderful Number Patterns Created by Yourself! Investigate what happens if we create number patterns using some simple rules.

Sisters and Brothers

Age 7 to 11
Challenge Level

Why do this problem?

This problem encourages children to use number operations and either trial and improvement, or a systematic approach to reach a solution. It would be interesting to share the different ways they use jottings to help during the problem-solving process. The problem could be used to introduce algebraic notation.

Key questions

What could you try to start with?
What does that tell you about the ages of the other children?
What do you know about David's age compared with Lachlan's age?

Possible extension

Learners could make up another similar problem for a friend to solve.

Possible support

You could ask questions such as 'what if Lachlan is one year old?' and encourage children to work out the ages of Cassandra and David to see whether all the information holds true. If not, invite learners to suggest what to try next.