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Part the Polygons

Age 7 to 11
Challenge Level Yellow star
  • Problem
  • Student Solutions
  • Teachers' Resources

Why do this problem?


This activity gives pupils opportunities to explore using trial and improvement. However, using some visualising and planning before tackling the problem will lead to a more considered solution.

Possible approach

There will need to be an assurance that the pupils are happy with the names as outlined in the question.

This problem can be presented to the pupils in an individual way with them having their own copies of the picture. (You could print off this sheet .) However, many children will benefit from working collaboratively and therefore being able to discuss each others' ideas.

You could use the interactive whiteboard to annotate the picture during a plenary.

Key questions

Tell me about the place where you've drawn your line.
What have you separated?

Possible extension

Ask the pupils to set out shapes in a different way that still requires three lines to group them. What is their method for doing this?


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Little Boxes

How many different cuboids can you make when you use four CDs or DVDs? How about using five, then six?

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The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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