When the class project on coral reefs accidentally falls into the aquarium, everyone is upset. They had all worked hard to create Ms. Frizzle's Big Book on the Great Barrier Reef. Now their reports are soggy and smeared. Tim is especially disappointed - some of his best artwork was in that book. But never fear, Ms. Frizzle always has a solution, and it's called a field trip. When the class climbs on board the Magic School Bus, they are headed down under. And they'll dive deep into the wild wonder of coral reefs.