Imagine learning about the human body by observing the different systems--circulatory, respiratory, skeletal, muscular, and more--right next to a cute, blue monster named Mo. Readers of this book will do just that! They, and Mo, investigate how the body works through examples of athletes throwing a shot put, hearing the starting beep of a swimming event, and mid-judo throw, among other examples. Short activities and questions keep readers engaged as they encounter important science curriculum content.