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Let Us Reflect

Age 7 to 11
Challenge Level Yellow star
Primary curriculum
  • Problem
  • Getting Started
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You will need a mirror for this activity.

Here is a square:

Where can you put the mirror across the square so that you can still 'see' the whole square?
How many different positions are possible?
How many lines of symmetry does a square have?

Can you reflect part of the square so that you can see a smaller square?
A rectangle? A kite? A hexagon? An octagon?
What do all the shapes have in common?

This problem has been adapted from the book "Starting from Mirrors" by David Fielker, published by BEAM Education. This book is out of print but can still be found on Amazon.


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Times

Which times on a digital clock have a line of symmetry? Which look the same upside-down? You might like to try this investigation and find out!

Transformation Tease

What are the coordinates of this shape after it has been transformed in the ways described? Compare these with the original coordinates. What do you notice about the numbers?

Penta Play

A shape and space game for 2, 3 or 4 players. Be the last person to be able to place a pentomino piece on the playing board.

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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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