In a math land far, far away, live the itty-bitty, teeny tiny, Tumblers. Each day, they roll out from their math homes to go to school. As Eva daydreams the adventures of these tumblers from her own math class, she learns the importance of counting, recounting, never giving up, and drawing to help her solve math problems. This part-part whole story helps young mathematicians practice breaking apart numbers, visualizing math stories, and reminds them that mistakes are a part of learning.