In the stereotypical high school community of John Hughes High in Southern California, sexy Priscilla, a popular cheerleader, separates from her football star boyfriend, Jake Wyler. After Jake discovers that Priscilla is now dating peculiar Les just to spite him, one of Jake's friends, Austin, suggests seeking retribution by turning Janey Briggs, a "uniquely rebellious girl", into the prom queen.

Jake attempts to court Janey's love, but faces adversity from his own sister, Catherine, who is sexually attracted to him; Janey's unnoticed admirer and best friend, Ricky Lipman; and memories from his past football career. Catherine eventually assists her brother by slightly altering Janey's appearance (by simply removing her glasses and ponytail), instantly making her drop dead gorgeous.

Meanwhile, Janey's younger brother, Mitch, and his friends, Ox and Bruce, make a pact to lose their virginity by graduation despite still being in their freshman year. Mitch tries to impress his longtime crush, the beautiful yet perverted Amanda Becker with a letter professing his love for her. Bruce says that he does not have a chance with her, mockingly stating, "Keep dreaming!"

As the prom draws near, Jake draws infamy among his peers after he fails to lead his football team to victory at the state championship game the year before. The situation is further worsened when Austin tricks Jake into telling Janey about his plan to spite Priscilla by pretending to whisper the secret bet in Janey's ear, causing her to immediately leave Jake. During prom night, Austin and Janey go together; a jealous Jake and Catherine have a dance-off with Austin and Janey, with Catherine dancing in a sexual manner. Janey runs off crying. Meanwhile, Mitch and his friends are having a lousy time at the prom until Amanda arrives and Mitch gives her the letter and Ox later hooks up with Catherine.

Jake is awarded prom king and the principal reads out that the votes for prom queen are tied. Everyone thinks that it is between Janey and Priscilla, but they are shocked to find that Kara and Sara Fratelli, twins conjoined at the head, win prom queen. During the traditional prom king and queen dance, Janey supposedly left with Austin to go to a hotel.

Jake goes to the hotel room where he finds Austin having wild sex with a girl but is shocked to find that it is Priscilla not Janey while the weird Les videotapes with his pants down supposedly having an erection, Austin tells Jake that Janey "ran home to her daddy". Jake angrily punches Austin and Priscilla, knocking them out cold, for what they had done to Janey. He then punches Les for "being really weird" (he also punches a plastic bag that happens to be floating next to Les); afterwards he runs to Janey's house only to learn from her father that she is going to Paris for art school.

Jake arrives at the airport and confronts her before she can board the plane, and uses a plethora of clichéd lines from other movies (such as She's All That, Cruel Intentions, American Pie, The Breakfast Club, American Beauty, 10 Things I Hate About You, Can't Hardly Wait, and Pretty in Pink) to convince her to stay in America. His final (and only original) speech suggests they would be better off apart, but Janey mistakenly believes he is quoting The Karate Kid, and she decides to stay with him.