Lisa finds herself unable to do any sports in PE class, taught by Brunella Pommelhorst, and finds herself failing physical education. She then signs up to do gymnastics with Coach Lugash. There, she receives encouragement from the ghost of John F. Kennedy in a vision. With boosted self-confidence, and her large head which gives her perfect balance, Lisa passes with flying colors. Lisa also meets two girls and becomes friends with them, but with their fractals and parking permits, she realizes they are college students "with small gymnast bodies!" They give Lisa a ride home, and she acts like a college student to keep their friendship. The two girls invite her to a poetry reading by Robert Pinsky soon after. Lisa begins to wear a beret to help her fit in better.
Meanwhile, Bart gets bitten by a Chinese mosquito that was in his Krusty-saurus toy, and becomes infected with "Panda virus". To prevent others from getting sick, Dr. Hibbert puts Bart in a plastic bubble. Bart has trouble adapting to life in the bubble even though Hibbert emphasized just how "normal" it would feel; he has trouble eating and Homer gives him a bath by filling up the bubble with the hose and rolling Bart around outside of the house. Lisa is able to keep up her double life, attending a poetry reading by former Poet Laureate Robert Pinsky at night and attending her second grade class during the day. While going to Springfield University, she is tracked by Milhouse, Martin, and Database when Milhouse saw Lisa ride away. At a lecture about Itchy & Scratchy cartoons, Milhouse blows Lisa's cover and she is no longer welcome by her college friends.
Lisa tries to convince Homer and Marge that college suits her, but they refuse to listen, saying that college is no place for her. Lisa is also ridiculed by Groundskeeper Willie and all of her friends at school, saying that she is too "college for them". In the meantime, Bart gets used to his bubble, as it brings him a lot of popularity. Bart tells Lisa what she should do to get her friends back: she has to pull a prank on Principal Skinner. The next day, Chalmers is dedicating the Seymour Skinner parking annex. While Martin takes pictures of Skinner posing next to a giant chocolate cake in his dress polyester, Bart rolls Lisa (inside his bubble) to the edge of the school's roof. He then pushes her over the edge, splattering the cake all over Skinner. Lisa gets her friends back, while Bart goes paranoid after being outside of his bubble for the first time in days. He stays in an air vent, but gets sucked in.