Questions kids ask about the world around them are answered in this series. The wonder of the world we live in is brought to life with striking full-color photographs and clear, easy-to-read text.. Set of 16 books: All About Light, All About Sound, All the Colors of the Rainbow, Light, Look How it Changes, Looking Through a Microscope, Looking Through a Telescope, Push and Pull, Scientists Ask Questions, What Is Electricity?, What Is Gravity?, What Is Mass?, What Is Matter?, What Is Velocity?, What Magnets Can Do, You Can Use a Balance. Levels F-I, Grades 1-2. Set includes 16 books