Kids will learn about the history of tunnels with Engineer It! Tunnel Projects. They will discover how tunnels are built. Then, build their own train tunnel, underwater tunnel, and more. Each project has color photos and easy-to-follow instructions. Young crafters will be budding engineers in no time!Aligned to Common Core Standards and correlated to state standards. Applied to STEM Concepts of Learning Principles. Super Sandcastle is an imprint of Abdo Publishing, a division of ABDO.