Lisa befriends some college girls who are unaware of her age. At home with their heady intellectualism and always seeking acceptance, Lisa pretends to be enrolled at their school. She spends most her time on campus while going to great lengths to avoid having her cover blown. When the truth is finally revealed however, she realizes that her old life suited her just fine.

Meanwhile, Bart is relegated to living in a bubble when he's bitten by a contagious mosquito.