Discover Musical Instruments Discover the harmonica in this simple and engaging book for curious kids. Beginning level texts introduce young readers to common musical instruments. Each book in this series explains how a musical instrument works and how it is played. Simple sentences encourage kids to learn more about music and to learn to play themselves. Sample text: The harmonica is a type of wind instrument. Harmonicas are also called mouth organs. Each book in this Discover Musical Instruments features brilliant photos to aid comprehension, a word list and additional features for teachers and caregivers.