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The game provides a powerful and engaging context for working on properties of triangles/quadrilaterals. Two other related problems are Quadrilaterals Game and Property Chart
This game can easily be played in groups. The rules are clear: after a brief demonstration students could be left to play the game. To encourage discussion and peer support, ask students to play as pairs; both must agree on the "final answer" before it counts. Again, to spread ideas and strategies around the class, you could organise a rotation or two so that all pairs move on and play a new pair.
Share out two or three sets of the cards (or big A4 versions) among all the students in the class, show a triangle on the board and ask students to stand if they have a card that describes it. The duplication of cards should generate useful conflict if people with the same card disagree.
It might be useful to have a worksheet available with lots of different triangles as 'ideas' or to save some students having to draw the shapes.