Bob and his team are building a roller-coaster. They plan it using DUPLO bricks. Spud wants to get straight to building and while going off excitedly he knocks over Birds' house. He uses the bricks Bob used for his plan to build a new birdhouse, but it is not structured well and falls over. Wendy helps him re-build it while Bob finishes the roller-coaster. Bob, Wendy, and Spud all test ride it.