Full of lively answers to all those tricky questions about how the world works, I Wonder Why books are a terrific way to keep young minds buzzing. With information and quirky facts to explain everything from 'What's the quickest way to knock buildings down?' to 'How much can a crane lift?' I Wonder Why Tunnels are Round will amaze, satisfy, and inspire. Sample questions: What holds up the ceiling? How do you wreck a building? How do you clean up all the mess? Which building is inside out?
