From the co-creator of the New York Times bestselling Ladybug Girl series comes a joyful counting book about inclusivity, play, and the thrill of making new friends--from one to ten and back again. A quiet day at the playground turns into a boisterous park-wide adventure as one boy on the slide becomes two kids on the see-saw, then three jumping rope. Before long, ten new friends are playing like they've known one another forever...