encourages pupils to explore angular properties of triangles. It leads into predicting what properties all triangles have in common.
Invite learners to tell you what they know about triangles. Use what they say to lead into the task: provide each pupil or pairs or pupils with three pieces of suitable stiff paper or card, a ruler, pencil and scissors and ask them to cut out three identical triangles.
Then, together as a group, explore putting the triangles together including the way suggested in the challenge.
Lead a discussion about what they notice and encourage any further ideas for exploration.
Tell me about what's happened (when the three triangles are put together as in the challenge).
Have you tried other sets of three triangles?
What else could you explore?
Learners may need help with the drawing and cutting.