As Bart and Milhouse watch an episode of South Park, Marge suddenly turns off the TV and makes them watch a show that’s more life-affirming on PAX-TV. Horrified, the boys run off. Bored, Bart comes up with the idea of tying a string around a fly to see where it goes. The fly eventually lands inside the Flanders’ home. The boys climb through the window, where they discover the Flanders’ cat ate the fly. Realizing no one is home, the boys decide to have fun. They end up racing a TV cart down a flight of stairs…and crash into a door, revealing a secret room. Inside is a virtual shrine of Beatles memorabilia. The boys drink some old Beatles soda and end up feeling woozy. Moments later the Flanders return home. Seeing the ransacked house, Flanders orders everyone into the panic room, where they call the police.

When Wiggum and his men arrive, Bart and Milhouse try to escape by hiding behind a cardboard cut-out yellow submarine. They knock into a drum set, alerting the police to their presence. When Marge finds out what happened, she tells Bart he’ll remain under her watchful eye from now on. She decides to place Bart in a supervised activity, and chooses the Pre-Teen Braves. Bart objects, labeling the group “geeky.” Soon after, Lisa suggests that Homer lead Bart’s tribe, and he accepts the challenge. Before long Homer assigns everyone in the group a tribal name. Then he decides to introduce them to Native American life by sitting on the couch and watching a football game. Marge and Lisa notice Homer’s indifference and decide to take matters into their own hands. Soon after, they make smoke signals in the backyard. Bart and his fellow Braves are so impressed, they ask Marge to be their new leader. Homer steps aside and lets Marge take over.

One night she gathers the group around a campfire, where they speak with an Indian spirit…whom Bart recognizes as Lisa. Later Marge introduces the boys to a genuine Native American, Jim Proudfoot, who explains how the once-rich land has been shattered by commercialization. Guilt-stricken, Marge drives the boys to a wooded area to pick up litter. She soon realizes that another group, the Calvary Kids — which is comprised of Milhouse, Martin, Jimbo, and others — beat them to it. Bart accuses Milhouse of betraying him. Marge comes to realize that the Calvary Kids take credit for just about everything, and decides to give them a run for the money by having her group earn the candy-selling merit badge. Homer steps in and launches a campaign of his own…by switching the Calvary Kids’ candy with laxatives. When people throughout Springfield buy the confections, they feel the sudden urge to use the bathroom. Customers soon begin buying from the Braves. When all is said and done the Calvary Kids make more sales…by selling the laxatives to old people.

Bart decides to give up, but Homer refuses to let his team be beat. When the Calvary Kids show up at Duff Stadium to perform the national anthem, Homer tricks them into parking far away. Then Bart and the other Braves enter the stadium dressed as their adversaries, where they sing a deliberately bastardized version of the national anthem. The crowd erupts in a rage, but the real Calvary Kids show up and a fight breaks out between the two groups. The fighting soon extends to the stands, and an all-out riot erupts. A TV cameraman catches Marge crying, and her sadness is soon broadcast on the stadium’s Jumbotron monitor. Everyone decides the fighting must not continue, and decides to sing the more-soothing National Anthem of Canada instead.