Milhouse and Bart are watching South Park on Comedy Central. The South Park Kids are watching Farty the Crippled Robot. The Robot Farts O.J. and he starts stabbing people. Marge changes the channel to PAX-TV and Bart and Milhouse scream. They are bored and go outside. Bart ties a string to a Fly and the Fly spots a sandwich in Ned Flander's window. The fly goes through the open window. Bart and Milhouse follow it. The cat ate the fly and Milhouse and Bart realize they are alone in Ned's house.
Bart: "Dude we're in Flander's house…..unsupervised." They start going through things in the house. Milhouse messes with the lamps, Bart sees a picture of his Family in Flanders house. Bart finishes their peanut butter. Then Bart and Milhouse try to make peanut butter by putting peanuts and butter into a blender without a top on. Bart and Milhouse sled through the house on a VCR rack and fall downstairs into the basement. They discover Ned's Beatles collection and drink 40 year old soda and begin to hallucinate about the Beatles. Ned, Rod and Tod come home to find their house a mess. They run to the Panic Room pushing the Police alarm and locking the door. They sing camp songs together. Chief Wiggum and the police arrive. Bart and Milhouse continue to make a mess in the basement while Chief Wiggum comes looking for them. Chief Wiggum confuses the Beatles with the Monkeys. Chief Wiggum says he's going to call their parents. Marge and Homer show up at Ned's basement. Wiggum asks Ned if he wants to press charges. Ned says Bart and Milhouse need Adult Supervision.
Marge, Homer and Bart are back home and they are deciding what activity Bart can do to keep him out of trouble. The Pre-Teen Braves is suggested and Homer is going to be the tribal leader. He does a drum solo and pounds everyone in the head. Homer ends up on the couch with the "tribe" watching football. Nelson smells smoke and the tribe runs outside to see Marge creating smoke signals. They all want Marge to lead them instead of Homer. Nelson is having dreams of his father returning and ends up hugging a tree.
Nelson: "Papa, is that you…you came back from the store!! Papa, Papa, never leave me again!!" (Nelson hugs a tree)
Marge introduces them to a real Native American, Jim Proudfoot from the Mohican Tribe. He shows the tribe that his land was vast and went from Krusty Burger to Gary's Waterbed Warehouse. The land was beautiful but now the land weeps. Homer is seen throwing a treadmill in the stream with all the other garbage.
Homer: "I'm giving it back to the Earth. "
Lisa tipped off the local paper to report the Tribe cleaning up the land. The land is cleaned…cleaned by the Calvary Kids. The Calvary Kids is a rival pre-teen organization with Milhouse and lead by Milhouse's Dad. The two groups are at war with each other. The Calvary Kids are on the front page of the Springfield Shopper because they cleaned the land. The Pre-Teen Braves visit the Springfield Retirement Castle and so do the Calvary Kids and they compete to entertain the elderly residence. Then they compete with giving food to the homeless, and finally they compete by building a house. The Calvary Kids knock down the Pre-Teen Braves house and then the Pre-Teen Braves set the Calvary Kids house on fire with fire tipped arrows.
On TV, Drederick Tatum issues a challenge to all the youth groups of Springfield in a Candy Selling Contest. The winner gets to do the National Anthem at the baseball game as honorary batboys for the Springfield Isotopes. Homer wants to be the tribal leader for the candy selling challenge. The Pre-Teen Braves place laxatives in the Calvary Kids candy bars. Lenny and Carl get sick from the laxative. The Calvary Kids outsmarted the Pre-Teen Braves and sell the candy to the Retirement Castle. The Calvary Kids win the challenge and get to sing the anthem at the ballgame. On the way to the game Homer tricks Milhouse's dad to park his car in the wrong spot with a homemade sign. Then Homer is drinking beer just because the Duff sign tells him to. The Pre-Teen Braves dressed as the Calvary Kids sing the National Anthem with made up words. The real Calvary Kids show up and a huge brawl erupts at the stadium. Everyone jumps in including Drederick Tatum. Marge starts to cry and she's put on the Jumbo-Tron. When they see her crying they all stop fighting and sing the National Anthem of Canada.