A young man's first sexual explorations are threatened by a string of murders.

Ponce de Leon Harper, a student at Los Angeles' Oceanfront High School who is obsessed with sex although he has never had it, asks to be excused when he cannot concentrate in a class led by a sexy substitute teacher, Miss Betty Smith. After taking refuge in the boys' restroom, Ponce finds the corpse of Jill, a cheerleader who has been murdered, in the neighboring stall. Pinned to Jill's underpants is a note reading, "So long, honey." Upset, Ponce runs past assistant principal Michael "Tiger" McDrew's office, which has a lit sign over the door indicating that "testing" is in progress. Behind the locked door, Tiger, who is also the guidance counselor and football coach, is having sex with one of the students. When Ponce informs the principal, prim Mr. Proffer about Jill's demise, Proffer contacts the police chief, John Poldaski. The racist Poldaski is inclined to suspect student Jim "Greenie" Green, because he is black, but would rather discuss the football team. Soon Capt. Sam Surcher, an investigator for the state police, takes over the case with his two colleagues. Although annoyed by Poldaski, who has detached the note from the corpse and allowed the crime scene to be trampled by curious onlookers, Surcher is honored to meet Tiger, who is a champion in several sports and is being sought by the university to teach psychology. While Surcher and his colleague Follo proceed with the investigation, Ponce, who is the football team's student manager, reveals the frustration of his relentless sexual urges to Tiger. Afterward, Tiger returns to his office to mate with another coed and later has the energy to romance his wife Jean at the beachhouse he shares with her and their young daughter. To learn more about Jill's life, Surcher talks to students Hilda Lee and Yvonne Millick, who imply that their generation is sexually unrestrained. Surcher also questions Tiger, who has been dictating on a tape recorder a book he is writing about his philosophy of unrepressed education. Tiger makes an appointment with sex-starved Betty, causing her to believe he is interested in her, but then asks her to "help" Ponce, whom he says is impotent and needs an adult woman's guidance. Continuing his investigation, Surcher asks students Sonny Swingle and Pamela if anyone on campus has made "unnatural sexual advances," to which they respond with laughter and evasion. Following Tiger's instructions, Betty invites Ponce to her home to discuss his schoolwork, where her close proximity arouses him. Aware of his erection, which indicates to her that he is overcoming impotence, Betty compliments it to encourage him not to feel ashamed. Believing she has succeeded in her task, she sends the baffled and embarrassed Ponce home. Later, Surcher finds a letter written to Jill, which he believes was written by Greenie. Tiger confirms that the letter was written by Greenie, whose alibi places him near the boys' restroom at the time of the murder, but insists that the student is not the killer. After hearing Ponce's account of the night before, Tiger urges Betty to offer another invitation to the boy, but she is reluctant, admitting that, having had no boyfriend for thirteen months, she feels attracted to Ponce. Tiger dallies with Betty, kissing and fondling her, then suddenly stops, declaring that she understands the "general idea." When he then opens the door for student Pamela to enter, Tiger suggests that they can talk more after Betty meets with Ponce. Tiger coaches football practice, during which Surcher takes note of his many female admirers. Afterward Tiger has a rendezvous with another student, who, during foreplay, informs him that she wants to be closer and knows he was intimate with Jill. The next day the student is found dead with a sign saying, "Keep cool, honey," pinned to her clothes. When the teachers meet to discuss cancelling an important football game because of the murders, Tiger vetoes the idea. Increasingly suspicious of Tiger, Surcher listens as he coaches students in a reading of Don Juan . Embarrassed about the previous evening, Ponce calls on Betty and awkwardly presents her with a chocolate duck filled with liquor. Later that evening he returns, and although dressed for bed in a revealing gown, Betty invites him in and then seduces him, pushing him onto a table to kiss him passionately. When Ponce smashes the chocolate duck laying there, soiling his pants, Betty washes his clothes and helps him bathe. Meanwhile, Tiger is making out with a student in a car parked on the football field, when Poldaski, who is patrolling, spots him. In the morning, as Ponce and Betty embark on another round of sex, Poldaski and the girl are discovered dead on the playing field, the latter bearing a note that reads, "Poor, poor honey." Reporters flock to the school, where everyone is concerned about the murders and the upcoming game. While parents demand an end to the murders, Hilda has a counseling session in the nude with Tiger. Surcher confides his suspicions about Tiger to Follo, who suggests that the captain is simply jealous. Hoping to catch Tiger in flagrante delicto , Surcher breaks into his office while the "testing" light is on, but finds Tiger and Ponce deep in discussion. After Surcher apologizes and leaves, Tiger tells Ponce that he hopes to be principal at Oceanfront someday and that Ponce will be his assistant principal. When Tiger returns home after school, he, Jean and their daughter fantasize about owning a boat and going to an exotic locale. On the day of the big game, a mass funeral is held for the victims. Between the funeral and the game, Sonny slips into Tiger's office and takes a Polaroid photo of herself in the nude and then records a message on his tape recorder directing him to look in the drawer in which she has hidden the snapshot. When Tiger walks in on her, the machine is still recording while they have sex. Spying on them, Surcher sees them leave the office separately to go to the game. By half-time, Oceanfront is far behind their rival team. Proffer unsuccessfully attempts to lead a moment of silence in memory of the deceased, while, in the locker room, Tiger rails at the team to do better. During the final half, Oceanfront repeatedly scores and wins the game. While Tiger is detained by fans and reporters, Ponce waits in his office and inadvertently discovers, and then listens to, the tape documenting the sounds of Tiger and Sonny's coupling. When Tiger arrives, he snatches the tape and announces he will drive Ponce home. Meanwhile, Surcher orders his men to pick up Tiger and several of the female students for a lie detector test. That night, while parked on an ocean pier, Tiger explains his philosophy to Ponce that sex is the best way to "reach" girls, while he uses sports to relate to the boys. When Ponce, who is frightened that Tiger will kill him, reminds him that he murdered the girls, Tiger admits that was a mistake and tries to justify his action. Acknowledging that Ponce cannot remain silent about what he knows, Tiger drives the car into the ocean. Later, when a memorial service is held for Tiger, he is lauded for his many contributions, including saving Ponce's life by thrusting him out of the sinking car. As Tiger's body was never found, Surcher remains skeptical and carefully watches Ponce and Jean, both of whom exhibit a secretive excitement. When Jean opens her purse, Surcher briefly glimpses Brazilian Airline tickets. After the service, a sexually confident Ponce consoles female students, one by one, suggesting that Tiger would want them to comfort one another. Surcher tells Follo that he was obviously wrong about Tiger and that he needs a vacation in Brazil.