A team of teachers from the same New York City public school met to discuss and compare the Common Core State Standards for Mathematics (CCSSM) to their current math curriculum. The group consisted of four kindergarten teachers, a representative from the first-grade teaching team, and the school's math coach. During the first meeting, the first-grade teacher expressed a concern that many first graders relied on "counting up" to solve addition problems. She explained to the group that students who could not understand the commutative property when they arrived in September struggled when increasingly advanced addition strategies were taught. The goal for the group became clear: To find areas of the CCSSM that would provide opportunities for kindergarten students to build a strong foundation for advanced addition strategies. This article presents how the composing and decomposing small sets of objects can allow young students to see the whole group as well as the subsets that created the whole.