Great for developing number sense within the context of ten. Using ten frames can encourage subitizing, help develop a sense of magnitude, show one-to-one correspondence, build number sense, improve understanding of base ten, and demonstrate strategies for composing and decomposing numbers. Ten frames are a versatile tool for addressing individual state standards, as well as addressing the CCSS. Interlocking foam Ten Frames can be connected with the Learning Advantage Five Frames (#7406 sold separately) to reinforce number relationships. Warning Choking Hazard Small Parts not for children under 3 years. Each set includes 4 interlocking foam boards with 40 two-color foam pegs. Bundle includes 3 sets.