How do rockets really work? From the moment a rocket ignites on the launch pad to the instant it reaches orbit, every part of the journey obeys a handful of powerful laws of physics - laws that were understood centuries before the first rocket ever left the ground. How Rockets Work takes readers ages 9-12 on a clear, fascinating journey through the science and engineering behind the most powerful machines human beings have ever built. Starting with Newton's three laws of motion and building through propellants, combustion chambers, staging, orbital mechanics, guidance systems, and solid rockets, this book explains the real principles behind spaceflight in plain language anyone can follow. Readers will discover why liquid hydrogen makes such an excellent - and dangerous - rocket fuel, how the tyrannical rocket equation forces engineers to make every gram count, why reaching orbit means going sideways rather than straight up, how gravity assists let spacecraft gain speed for free, and why reusable rockets like the Falcon 9 are transforming the economics of reaching space. Packed with accurate science, real engineering history, and the stories of the rockets that changed the world - from the V-2 to the Saturn V to Starship - this is the book for every young reader who has ever watched a rocket launch and wanted to understand exactly what is happening, and why.