Students stack number tiles on their favorite "monstermatic" as they solve a variety of problems to win! Game uses numbers 0 to 20 and the four operations to help students develop calculation skills. Play at 2 different ability levels. Includes 4 monstermatics, 73 number and operations tiles, and game guide. For up to 4 players. Ages 5+. Grades K-3. Watch the Monstermatic ® demonstration!