Each Koplow Games 6 Function Math Operator set contains 3 dice with 6 function math operators and 3 dice with corresponding English words. Children learn more effectively when it is reinforced through play. A fun, hands-on way for students to learn basic math operation. These dice help keep children's attention and interest. Perfect for individual play, in small groups or as a classroom. Dice measure 20mm. Each set includes 6 dice.