Play the game in 4 teams. Each team chooses a name.   1  Draw a grid containing 20 squares on the board (4x5), five in each row. Write the numbers 1-20 in each square. Put a memory card in each square, face down. 2  The teams take turns to pick any two cards. 3  The teacher turns over the cards. 4  If the two cards match, the team gets a point. If they are not, the next team plays. 5  The game is over when all the cards have been matched and the winner is the team with the most matches.