This set of foam dominoes can be used as simple flash cards for practicing and reinforcing concepts in measuring area and perimter, or as a game for up to four players. It includes two sets of 24 colour-coded dominoes (48 pieces in all), with one set focusing on calculating the area of squares and rectangles and the other on measuring the perimeter of a variety of shapes. Each domino measures 8 cm x 4 cm (about 3" x 1 1/2"), and the set comes with instructions and activity suggestions.