After Bart and Lisa inform Homer that his taste in music has become old, he decides to get into the current music scene and takes the kids to a music festival, Hullabalooza, where he accidentally discovers he has a talent for taking a canon ball to the gut. Soon Homer finds himself traveling with the festival and putting his health in danger as he continues performing his amazing feat for cheering crowds.
Otto dreams that he won the award for the School District's safest Bus Driver. Unfortunately, he dreams about it while driving the school bus. Milhouse then wakes him up, and swerves out of the road to avoid running down Jasper, and ends up plowing into an auto-wrecking yard. Otto also ends up evacuating the kids and himself from the bus right when he stops right in front of a vehicle cube compressor, and ends up unintentionally turning the school bus into a bus-shaped cube. Despite Otto requesting that the students keep secrets about the incident, the faculty and staff ended up finding out anyways, to which, the next morning, Marge reads aloud the letter that explains that, due to the "unscheduled field trip" to the Auto Wrecking Yard, the bus is out of commission for two whole weeks.
Homer drives Bart, Lisa, Nelson and Milhouse to school. During the journey, he listens to a Grand Funk Railroad track and is shocked when the kids say that they've never heard of it. Eventually he goes to a music store and is shocked when his music is classified under the "oldies" section. To prove that he's cool, he takes his kids to the Hullabalooza Festival. After being humiliated, he is kicked out by the crowd and then out of anger, kicks a cannon which fires an inflatable pig which hits him in the stomach. The festival head is impressed at Homer's ability to take blows to the stomach and hires him for his freak show.
Homer travels around with the Hullabalooza crew for a while before going back for another tour date in Springfield. He is persuaded to go to a doctor who tells him that if he takes another cannonball to the stomach, he will die. As his place in the show approaches he decides to dodge the cannonball, which makes him unpopular again, but earns him the respect of his family back.