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For younger learners

  • Early Years Foundation Stage

Sticks and Triangles

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

I made some triangles out of sticks. The sticks are all the same length.

I can make a triangle out of three sticks:

triangle from 3 sticks


What about four sticks? Five sticks? Six sticks?

I can make two different triangles out of ten sticks:

two triangles from 10 sticks


Can you find any others?

What about triangles made from twenty sticks?

What about all the lengths in between?

Can you make any rules about the numbers of sticks that make the most triangles?

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Multilink Cubes

If you had 36 cubes, what different cuboids could you make?

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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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