A younger sibling’s curiosity about school opens up a world of possibilities in this ode to the great outdoors. Tomorrow is the first day of the new school year, and big sister Mona can’t wait to go back. “What do you do at school?” asks little brother Milo. As he listens to Mona recount the many things she does during the school week — riding the bus, practicing spelling and reading, learning about science, playing with friends — Milo’s activities illustrate that with a little imagination, nature itself can be a classroom. With delightfully naive artwork and a spare text, Toni Yuly shows that learning is play and vice versa, offering a gentle introduction to school for children who are just starting and a warm celebration for those who are going back.