Cut all the cards up so that the numbers (number of sides), diagrams and names are all on separate cards. Mix them up and hand them around the class so that each pupil has one card. Their task is to get into groups to complete a full set i.e. Square, 4 (sides), diagram of a square. They then have to come to the front and stick their answer on the board. If you want to make it a race then it’s up to you, I did this with year 9 set 3 (of 5) and they loved it.
Triangle
Quadrilateral
Pentagon
Hexagon
Heptagon
Octagon
Nonagon
Decagon
Dodecagon