Bridget and Willie go to Disney World to design a rollercoaster. They meet with professional engineers to learn how to design a coaster and about the forces and motion at work, including gravity and inertia. Then they build a physical model to try out their ideas. Finally, they program their coaster design and "ride" their creation in a full-motion, virtual reality simulator. Madi and Mike head off to a recording studio to work with a professional musician to record an original song.