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  • Early Years Foundation Stage

It's a Fence!

Age 5 to 11
Challenge Level Yellow star
  • Problem
  • Getting Started
  • Student Solutions
  • Teachers' Resources

Here is a man among the trees looking at where to put a fence. It's a circular fence.

Man in Wood

These diagrams show where the fence may go when the trees are planted in squares:

CirSq CirSq12 CirSq14


These diagrams show where the fence may go when the trees are planted in triangles:

CircTri15 CircTri16 CircTri13

So, let's start by looking at different examples of these circles and see what things we notice. Then we could decide what we could try out and explore!

This problem could be worked on in a group of about four. For more details about how you might go about doing this, please read the Teachers' Notes.


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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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