Didax Educational Resources Number Sleuth, Grades 4-5Number sleuth builds number sense! Children puzzle and play with numbers using essential math concepts. Children solve the problems featured on the challenge cards by circling the correct responses on their dry erase digit card. Instructions and ideas for multiple game variations included. Ideas for whole class or small group math stations also provided. Each set includes 60 double sided cards: 30 Challenge cards and 30 digit cards. Grades 4 5.