Seven Flipped
This challenge is quite tricky but children will find it a
motivating context in which to develop a logical, systematic
approach.
It would be useful to introduce the problem on an interactive
whiteboard so that the whole group can be involved with deciding
which mats to turn. Alternatively, cardboard mats coloured
differently on each side could be used and pinned to a board. This
initial whole group work will familiarise the children with the
"rules" of the problem so that they will be confident to find the
smallest number of moves in pairs.
It will be important for them to devise a recording system that
they are happy with, and this is something that can be addressed in
the introduction, for example by asking whether they would be able
to repeat the moves they made. Encourage them to think about odd
and even numbers of flips, and when they come to investigate other
numbers of tiles, you might expect them to generalise for multiples
of three at least.