Split the class into two groups. One group is red and the other is yellow. Decide which team will go first. Ask the first team a review question. If they get it right they put their color checker in one of the bottom slots. Repeat with the next team. If the team gets the answer wrong they lose their turn and the other team gets a chance to answer the question.
The object of the game is to connect four of your color checkers either vertically, horizontally, or diagonally.