1-2-3 OY! dramatically improves fast mental arithmetic, quickly builds confidence and encourages teamwork. Teachers, parents and students, remedial to advanced, here and abroad love this unique collection of ten dynamic math card games. The flexible rules and optional use of addition, subtraction, multiplication and division will challenge the best of the best and help the most math phobic. The instructions include comprehensive information for educators at both school and home. Each game is presented with numerous variations which are easily adapted to player´s abilities. Each game is clearly defined by grade level, difficulty and speed. Multiple Award Winner (Also check out the companion set of eight word games, A-B-C OY!)