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For younger learners

  • Early Years Foundation Stage

Polydron

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

Do you have any Polydron in your school?
Here are some questions about the square Polydron.


You can see in the picture that a square can be made in two different ways.
  • How much bigger is the one made from 4 right angled isosceles triangles than the one made from just one square Polydron?

 
Polydron is great for connecting and folding pieces together. 
Using only square Polydron you can can easily click them together to make other shapes.
If you connect five squares together we call it a pentomino.
There are 12 different ones.
  • Can you find them all?
  • Do all your pentominoes have the same perimeter length?
  • How many pentominoes have line symmetry?
  • Rotational symmetry?

What if you could fold them up?
  • How many of the pentominoes will fold up and clip together to make 'lid-less' boxes? Why not discuss first which will fold up and which won't, before trying to fold them?

You may also like

Tangrams

Can you make five differently sized squares from the interactive tangram pieces?

Geoboards

This practical challenge invites you to investigate the different squares you can make on a square geoboard or pegboard.

Tiles on a Patio

How many ways can you find of tiling the square patio, using square tiles of different sizes?

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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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