Change is good for everyone except Arnold, who's worried that a new teacher - Ms. Frizzle's young sister - will alter the class's "ecosystem".

A field trip to the world's windiest mountain helps Keesha and the class strengthen a set piece for a sequel to "The Three Little Pigs".

Ms. Frizzle takes the class to Hawaii where an overprotecting Wanda gets schooled when she's forced to think like a tiny little fish.

Tim pens an original comic book for the school's upcoming time capsule ceremony that pits Weatherman against Captain Rock Man. But who will win?

While visiting a mountain made of magnetite, Ralphie and the class shrink to subatomic size to get some hot tips for their disorganized dance troupe.

Carlos plans to convince the principal to let the students keep a pet rat in the classroom. But first, he'll have to stop sneezing.

Determined to outwit an old rival, DA applies the art of animal camouflage to a schoolwide game of extreme hide-and-seek.

A lesson on water and its three basic forms -- solid, liquid and gas -- inspires Jyoti's submission for a "3-in-1 Gizmo That Goes" contest.

An icy glacier's eye-opening birth story helps a data-driven DA -- who's not one for public speaking -- deliver a talk to a sold-out crowd.

The class constructs a giant robot with help from brainy scientist Dr. Sarah Bellum, then takes a look inside Ralphie's nervous system.

A skittish Arnold looks to alternative energy sources to help keep his fears at bay while camping outdoors with Ms. Frizzle and the class.

Ms. Frizzle turns the Magic School Bus into a submarine to take the class into the ocean's darkest depths and retrieve Jyoti's high-tech locket.