The human body is a complex—and remarkable—machine. Digesting our food. Pumping our blood. Walking, running, and dancing. It takes our many body systems working together to keep us alive and living our lives to the fullest. This set of True Books offers an in-depth look at our amazing bodies—one system at a time. Interesting information is presented in a fun, friendly way—and in the simplest terms possible—giving students a “behind-the-scenes” look at how their bodies work.