Counting and cardinality are key to building basic number sense in young mathematicians. Beginning with writing numbers to 10, the collection is organized so that each resource directly relates to, or builds upon, the previous one. Learners are able to count and write numbers all the way to 120 before learning how to skip count by 2s, 3s, 5s, and 10s. These skills all help build basic number sense in order to add and subtract. The collection includes helpful math tools, such as ten frames, hundred charts, and dot cards, that prove valuable in reinforcing these skills.