Principal Skinner closes the school a day before spring vacation and invents Go to Work with Your Parents Day to keep the students occupied. Bart spends his time with Patty and Selma at the DMV. When the sisters are distracted, he creates his own driver's license and uses the ID to get into an R-rated movie. Bart, Milhouse, and Nelson later run into Martin who has earned $600 trading commodities at his father's job. Armed with money, and the fake ID, the boys rent a car. Meanwhile, Lisa occupies Homer to the power plant and spends the day at his work station.

Bart, Milhouse, Nelson, and Martin tell their parents that they are attending the National Grammar Rodeo in Canada and sneak off for a trip in Bart's rental car. Scanning an outdated AAA guidebook, they chose Knoxville, Tennessee, as their Spring Break destination, planning to see the World's Fair, which was held there 14 years earlier. In Knoxville, their car is destroyed, and they are strabded without money or transportation.

Bart places a collect call to Lisa, who has spent the entire spring vacation with Homer at work, to ask her for advice. Lisa obtains Homer's promise that he won't get upset and reveals Bart's predicament. Homer orders equipment for the power plant and ships it via courier from Knoxville, with the boys stowed away in the crate.