Inspired by the London 2012 Olympic and Paralympic Games, BBC Two Learning Zone has produced a new series of video maths challenges for Key Stages 1, 2 and 3. Developed with input from us (the University of Cambridge's Millennium Mathematics Project), 3, 2, 1, Go! sees real schoolchildren solve problems given to them by Olympic champions and sporting heroes.

### Key Stage 2 - Gymnastics Lines of Symmetry Challenge

3, 2, 1, Go! is a sports-maths challenge show which reveals how important maths is to sport. Watch as two gymnastics-mad Key Stage 2 schoolchildren are taken to the Heathrow Gymnastics Club in Greater London. They meet Olympic hopeful Daniel Purvis, and are set a maths challenge related to gymnastics. It is very important for Daniel to make clean, symmetrical shapes with his body. The challenge is to take pictures of Daniel doing various moves and mark on the photos the shapes and lines of symmetry.

Possible uses in the classroom:

Set the scene by asking the children what gymnastics is and what sorts of events are included.

Gymnasts are given a mark by the judges. What are the judges looking for to give high marks?

Show the video up to where the challenge is given. Ask the children what sort of symmetrical shapes they think Daniel will make and make a record of them on the board. Show the rest of the video and ask the children if they can see any additional shapes.

In pairs, the children make as many different symmetrical shapes with their bodies as they can. They keep a record.

Bring the class back together and ask each pair to show their best shape. If you have a camera, take photographs which can be annotated for a display.

Extension:

Can they make pictures of any 2D shapes with more than one line of symmetry? What makes this difficult?

Can they make pictures of any 2-d shapes which have rotational symmetry? What might these look like?

Support:

Give children cards with named pictures of 2D shapes on.

They draw lines of symmetry on them, using a mirror if necessary, and then create the shape with a partner. Can they make each shape in more than one way?

Related resources

• National Flags is another Key Stage 2 activity which explores 2D shapes, angles and symmetries in the context of the many flag designs on display during the Olympics.
• Olympic Turns is a challenging activity aimed at older primary pupils at Key Stage 2. Look at photos of Olympic sports, including gymnastics: what angles can you see? Can you estimate them?

The following problems from our NRICH website explore the mathematical ideas encountered in this activity in more depth:

• Let's Reflect This accessible practical problem enables children to explore the line symmetry of 2D shapes and is aimed at KS2.
• Symmetry Challenge This slightly more challenging problem for KS2 requires learners to recognise and visualise the transformation of a 2D shape, and invites them to work systematically in a spatial environment.
• Exploded Squares This problem for younger children at KS1 helps to consolidate their understanding of line symmetry.
• Colouring Triangles This slightly more challenging problem for KS1 helps children recognise reflective symmetry and also push their own understanding of symmetry further.
• Shady Symmetry This problem is aimed at older students at KS3 and is a good activity for the visualisation of symmetry, and for encouraging learners to work systematically. There are many different avenues for exploration and extension, and learners' work can be used to brighten up the classroom walls.

Learning outcomes:

KS2 Maths Curriculum

{Ma3 2b} visualise and describe 2-D and 3-D shapes and the way they behave, making more precise use of geometrical language, especially that of triangles, quadrilaterals, and prisms and pyramids of various kinds; recognise when shapes are identical

{Ma3 2c) make and draw with increasing accuracy 2-D and 3-D shapes and patterns; recognise reflective symmetry in regular polygons; recognise their geometrical features and properties including angles, faces, pairs of parallel lines and symmetry, and use these to classify shapes and solve problems.

Commissioned by BBC Two Learning Zone with advice from Lynne McClure (Director of NRICH, Millennium Mathematics Project, University of Cambridge), the clips were produced in collaboration with BBC Sport.