Lift

This game is played on a 6x6 grid. One player puts 36 balls into the grid (3x12 of the same color). The pattern must be symmetric. Afterwards he/she covers the balls with 36 "lids". The other players now take turns lifting individual lids and checking the color. When a player thinks he or she knows the entire pattern, he or she makes a sketch on a piece of paper. After a number of rounds, the player with least errors wins.