The episode starts as Marge and Homer celebrate the start of the new year of school. (Even though the start of the episode depicts the start of a new year of school, Bart's class remains the same.)
Bart accidentally receives a perfect score on a practice test for the upcoming Vice President's Assessment Test, by writing "Slurp My Snot" across his page. This enables him to attend a pizza party by helicopter. However, it all proves to be a ship-of-fools ruse to purge the school of all bad test-takers. Bart actually failed the test and the helicopter is a disguised school bus. He, Nelson, Ralph, Kearney, Dolph, and Jimbo are driven to Capital City by Otto, along with Principal Skinner, who was pushed on board the bus by Superintendent Chalmers. On the way, Ralph stops for a bathroom break, and the bus is disassembled and stolen by vandals (while Otto is still sitting in it). The group attempts to walk the rest of the way, but they lose Ralph on a garbage barge. Skinner signals for a slingshot cargo ship to rescue Ralph with its crane, but he accidentally stuns the driver. Skinner rescues Ralph himself by jumping on board the Shipping Container hoisted by the crane and using the law of conservation of angular momentum. Eventually the container rotates into a position that allows Skinner, the boys, and Otto to run along its top and jump onto the barge. As it turns out, the barge is headed towards Springfield Elementary School. The boys now believe that education is impressive due to Skinner's saving the day, and so Skinner reads Adventures of Huckleberry Finn to the boys until they arrive, which they enjoy.
Meanwhile, Homer is late making an insurance payment, and will not be insured until 3:00 PM, so he cannot hurt himself until then. Images of injuries flood his mind when he gets home, envisioning Marge's book club being killed by a series of freak accidents (and Marge making out with Lindsey Naegle). He has to keep the entire book club safe while he is still uninsured, but ends up throwing a knife in Mr. Burns' head at 3:01 as he randomly walks onto the Simpsons' property. Marge, however, is pleased to know what Homer can and cannot do. At school, Lisa is unable to focus on the test, as the thought of Bart being smarter torments her. When the test ends, she has not answered a single question, along with the fact that the test is nearly impossible (the choices to a question's answer all mean the same thing, and there is a penalty for guessing). However, Skinner returns just in time to cancel the test and lift the school's "ban on dancing".