"Meets the Rot Squad" is the 6th episode of season one of the animated children's series The Magic School Bus. It originally aired on October 15th, 1994.
The class is having a "Most Disgusting Rot" Competition. When Wanda wins with a container with very disgusting stuff that's been in her fridge since she was four, Ms. Frizzle awards her with a small "Not Rotten At All and Full of Life" tree. She wants to plant it in an abandoned lot near her house. The class goes to the lot and finds a rotting log. At first, Wanda wants to get rid of it and build an amusement park called Wanda World, but Carlos and Dorothy Ann want to build a rot-themed one called Rot Land. Ralphie and Keesha want to build a restaurant, and Phoebe wants to build a recycling center, which Wanda quickly shoots down. Arnold, however, wants to leave the log as it is. At the lot, Wanda sees an ad for "Larry's Log Away" and calls. Ms. Frizzle then shrinks the class, and they go inside the log. After learning about what makes things rot and how they feed small animals and bugs, Wanda changes her mind. But when Larry gets there, they have to convince him not to destroy the log.
At school, the class have a "Most Disgusting Rot" competition, and Ralphie scores two nose-holds and a fainting person for his rotten orange. Phoebe earns a perfect nose-hold score for her rotten banana peel. It isn't until Wanda shows her most disgusting stuff that has been inside the fridge since she was four inside the container and opens the container to reveal very disgusting mold inside. Wanda ends up scoring three faints, thus winning the competition. Ms. Frizzle offers Wanda a baby tree planted in a pot as a prize. Wanda tells Mrs. Frizzle that she hopes it isn't rotten in any way, and Ms. Frizzle informs that rot is just as alive as the tree. Wanda decides to plant her new prize in an abandoned lot next to her house and Ms. Frizzle brings the class along with her to the bus to do so.
While the bus drives to the lot, the class try to convince her that the lot is replete with dead stuff. But Wanda tells them that it's the point, for everyone could collaborate and improve the lot's condition. Wanda decides to make a park called "Wanda World" once the tree grows in size. Carlos, on the other hand, suggests that they should make a big theme park called "Rotland". Keesha suggests that the class should build a restaurant, most notably a fast food joint. Phoebe, however, rejects the idea of both the restaurant and the theme park, saying that it would indict more garbage, and decides that the place should be a recycle center.
When the class finally make it to the lot, Wanda exits the bus and looks around. She asks for her classmates' assistance, But they are too busy on what they should make the lot into. So Wanda and Liz work together and come across an ad for "Larry's Log Away". Wanda runs to a pay phone and calls to ask Larry to get rid of the log on the lot.
When Wanda returns to the bus, Arnold suggests that the log should be left as it is, for if you leave nature alone, it'll get along just fine. Wanda tries to convince Arnold otherwise, giving Ms. Frizzle an idea. She shrinks the school bus to the size of a toy truck and the bus heads for the log. Wanda, realizing her mistake, begins to panic.
As the bus heads for the log, Ms. Frizzle informs Wanda that the class is going to find out what rot has to do with life. The bus comes to a stop in front of the log and the class exits the bus. They begin to climb the log and come across a chipmunk, which Wanda takes a ride on. She lets go and lands into Ms. Frizzle's arms. Wanda tries to convince the rest of the class to leave the log, only for the class to enter the inside of the log through a hole. When they navigate inside it, Wanda climbs back on top of the log to keep an eye for Larry. Just then, a woodpecker towers above Wanda, causing her to fall back inside the hole to join the class. Ms. Frizzle tells the class that woodpeckers only eat bugs. Carlos notices the amount of tunnels inside the log and the class come across a Bessie bug, who made the tunnels. Just then, the bus arrives and transforms into a Bessie bus. The class follow the bus and Tim gets stuck to a mushroom. Dorothy Ann informs that some mushrooms grow on dead wood and that underneath, a tangle of tiny threads grows throughout the wood. The threads eat the wood and help rot the log. Carlos suggests that the thread could be good for the haunted house in Rot Land. Just then, the woodpecker returns, and the class come across a bunch of bugs crawling through the inside of the log. Ms. Frizzle slides down through a slippery substance inside the log and the class slide down along with her. Ms. Frizzle informs the class that the slippery substance is slime, which also lives off the log. When Wanda tries again to convince the class to leave, Ms. Frizzle transforms the bus into a catering truck and serves the class lunch, only for the class to find that the "food" Ms. Frizzle is serving is really for the log, telling the class that the creatures inside the log use the log as food and energy. The class finally decides to leave the log as it is, saying that the log is already a restaurant for the bugs. Wanda, again, tries to convince the class to leave the log, but fails once again.
As the class makes their way to the end of the log, Wanda tells Phoebe and Tim that she would accept their recycling idea. But Phoebe and Tim tell her that the log is already being recycled, for it is food and fungi for bugs, as well as the bug plops being used for smaller bugs to munch on, much to Wanda's disgust. Ms. Frizzle tells her that it's just another addition to decomposition. When Wanda tries again to persuade the class to escape the log, Keesha notices soil and tells Wanda that it is perfect for her baby tree. After learning that the log is fine where it's at, Wanda finally makes a decision to not have it be taken away.
Unfortunately, Larry arrives, and attempts to saw the log with a chain saw. The class escapes back inside the log and Wanda gets an idea. She goes into the bus' trunk and offers the rest of the class bus suits. They enter the bus and Ms. Frizzle propels it out of the log and onto Larry's helmet. Wanda calls his name, distracting him. Wanda dangles off the edge of Larry's face and lands onto his nose to convince him of the log's nature. So he changes his mind of sawing the log and Wanda hops onto a flower and slides down through the stem and onto the ground. Larry finally leaves, and the log remains on the lot.
Back in the classroom, Wanda decides to take the bucket full of rot on the bus and the bus drives back to the lot. Arnold pours the rot in the soil with the tree buried in it and Ms. Frizzle tells the class that "It doesn't have to be nutritious to be delicious", causing the students to laugh.
- Ed Begley, Jr., who voiced Larry, played Stan Sitwell on the sitcom Arrested Development and Ned Kincaid on the Shining Time Station special: Once Upon a Time starring Thomas the Tank Engine. Fellow Arrested Development alum, Jessica Walter, who played Lucille Bluth, guest stars in "Rocks and Rolls".