Since his family has fallen on hard times, Allen Gregory De Longpre, one of the most pretentious 7-year olds of our time, is forced to face his greatest challenge - attending elementary school. His mature ways make it hard for him to fit in and his struggle to adjust is not limited to his classmates. As Allen Gregory makes his rounds with the faculty, his first meeting with his much-older principal takes a special turn.
After discovering that his rival classmate Joel Zadak has a girlfriend, Allen Gregory sparks a sex tape scandal with Principal Gottlieb. To help Allen's adopted sister Julie appear "normal," Richard and Jeremy hire cool-looking kids to hang out with her.
When Allen Gregory's doting - and comically malevolent - dad Richard helps plan Allen's first school dance, tension occurs when popular stud Joel Zadak invites Allen's trusty friend, Patrick and not Allen Gregory. Meanwhile, jealousy sparks when Richard's life partner Jeremy gets a job as a D.J. at Kirby's Roller Bowl.
When Joel Zadak stays home from school because he's sick, the always presumptuous Allen Gregory steps in to help his popular "friend" by keeping tabs on the clique. As Allen Gregory gains some ground with the exclusive group, Zadak loses more than his friends. Meanwhile, Richard hits the boardroom at his father's company.
Allen Gregory's teacher Gina seeks to teach him a lesson on racism after he mistakes his Hispanic schoolmate Guillermo for a janitor. Much to Gina's dismay, Allen Gregory produces a play to depict his point of view of the incident. Meanwhile, Richard hires Jeremy as his new maid.
Allen Gregory enlists the help of a friend to find his biological mother. Though Allen Gregory initially dreams of his mother and father falling in love and starting a life together, he soon realizes that this new "family" is not all it's cracked up to be.
The persistent and pompous Allen Gregory bribes Principal Gottlieb into a romantic situation that he hopes will bring them closer together. Meanwhile, Richard uses Julie to compete with his frenemy's adopted child.