Homer sees an advertisement in the newspaper for a free trampoline. He rushes to the address from the advertisement, where Krusty the Clown is giving it away, and brings it home. While Bart and Lisa are thrilled by it, Marge is concerned about the potential dangers. Homer brushes her worries aside; he has plans of turning their backyard into a theme park, and decides to charge a fee to use the trampoline. Inevitably, however, people start getting hurt, and Homer finally takes Marge's advice to get rid of the trampoline. After failing at his various attempts to do so, Bart steps in to help Homer. They chain the trampoline to a pole using a bike lock and wait for Snake Jailbird to steal it.
Homer and Marge argue later that night. Homer admits that while Marge was right that getting the trampoline was a mistake, he adds that he's at least willing to go out and try new things while she's bossy, boring and just nags all the time. Marge, of course, disagrees with this, but after asking Bart and Lisa what they think, she discovers that they agree with their father's assessment about her. Marge becomes offended that people see her that way and goes to her sisters' apartment. While at Patty and Selma's apartment, the twins introduce her to an infomercial featuring self-help guru, Brad Goodman, who can supposedly help people like Marge with their chronic nagging. After Marge encourages Homer to watch a Brad Goodman video with her, she becomes more tolerant and the two start getting along better. After seeing how out of control Bart is, the family goes to see Brad Goodman's live lecture in the hopes that it will change him. Bart interrupts the lecture, but Brad Goodman encourages the town to follow Bart's spontaneous attitude. Soon, the whole town starts acting like Bart, who at first enjoys things, but eventually becomes upset by it. Lisa explains that it's because he's lost his unique identity as a rebel with everyone else in town acting like him.
To celebrate their new-found attitude, the town holds a "Do What You Feel" festival. However, the festival soon goes awry because those responsible for building the stages and maintaining the rides "didn’t feel like" doing a thorough job, resulting in a runaway Ferris wheel causing chaos. Arguments begin, as everybody has been encouraged to always say exactly what is on their mind, and a riot soon breaks out. Bart is quickly blamed for starting the whole "do as you feel" trend, even with Reverend Lovejoy pointing out that Brad Goodman was the one who encouraged them to act like Bart in the first place. The town chases after him, prompting Homer to save Bart by driving in a float. Despite the very slow speed of the float, the town gives up the chase and goes to the old mill to get some cider. The Simpson family returns home, where they try to figure out what the lesson of the episode was. Homer claims that Bart should have been a better role model, but Marge comes to Bart's defense by saying that self-improvement is best left to people who live in big cities. But then Lisa says that self-improvement can be accomplished, but through hard work and not a quick fix. Homer concludes that they're all fine the way they are and the family starts to watch TV.