Pre-K & up. Illustrate numbers less then or equal to ten, and improve number sense within the context of ten. Ten-frame activities enable children to think of numbers less then ten in terms of their relationship to ten and to build a sound knowledge of the basic facts which are an integral part of calculations. Suggested activities included. Foam construction, magnetic backing. Set includes four magnetic boards and 80 pegs (40 blue and 40 red/blue).