Age 7 to 11 Challenge Level:
Why do this problem?
This challenge focuses entirely on visualising a process in your head, something which perhaps pupils have little experience of trying. Visualising in this way can be a very useful tool in solving problems, but of course children need to be encouraged to use it. Therefore it helps if they are given lots of opportunities to do so.
A good way to carry this out with young pupils is to set up a straight line on a small, maybe 4 x 4, dotted grid on an OHP sheet and quickly show them the flips required. To introduce this activity in the classroom, give everyone time to picture the flip for themselves, in silence first. Then ask them to talk to someone sitting near them about it. Can they describe where the F or triangle will be
on the grid without drawing it and without gesticulating? Once they have had a chance to do this, share the descriptions with the whole group, again discouraging drawing and gesticulating! (Think-pair-share.) Talk about the effective ways that pupils have found to describe, not only the process and how they imagined it, but the final result.
It will help some pupils to provide them with a sheet of dotted paper once they have got an answer and have told someone about it, so that they can record their visualisation. You may find that others are able to rely completely on their own "mind's eye" and verbal descriptions.