It is May 28, 1976, the last day of school at Lee High School in the suburbs of Austin, Texas. The next year's group of seniors are preparing for the annual hazing of incoming freshmen. Randall "Pink" Floyd , the school's star football player, is asked to sign a pledge promising not to take drugs during the summer or do anything that would "jeopardize the goal of a championship season." When classes end, the incoming freshman boys are hunted down by the seniors at the local junior high school for paddling. The incoming freshman girls are also hazed as they are rounded up in the school parking lot by senior girls, covered in mustard, ketchup, flour, and raw eggs, and forced to propose to senior boys.
Freshman Mitch Kramer escapes the hazing with his best friend Carl Burnett when Carl's mom pulls a shotgun on Fred O'Bannion but is eventually cornered at his baseball game, where he is violently paddled. O'Bannion, a senior participating in the hazing tradition for a second year after failing to graduate, takes special pleasure in punishing Mitch. Pink gives the injured Mitch a ride home and offers to take him cruising with friends later that night. Plans for the evening are ruined when Kevin Pickford's parents discover he is to host a keg party. Elsewhere, the intellectual trio of Cynthia Dunn , Tony Olson and Mike Newhouse , known as the class nerds, decide to go out and "viscerally" participate in the evening's activities. Pink and his friend David Wooderson , an older guy who still socializes with high school students, pick up Mitch and head for the Emporium, a pool hall popular with the teenagers.
As the evening progresses, students loiter around the Emporium, listen to rock music, cruise the neighborhood and stop at the local hamburger drive-in, Top Notch Hamburgers. Mitch is introduced to sophomore Julie Simms , with whom he shares a mutual attraction. Then, while cruising again with Pink, Kevin, and Don Dawson , Mitch drinks beer and smokes marijuana for the first time. They play mailbox baseball, but a neighborhood resident brandishing a handgun catches them and threatens to call the police. They barely escape, but not before the resident fires at their car, narrowly missing. After returning to the Emporium, Mitch runs into his middle school friends. They hatch a plan to get revenge on O'Bannion, who continues to haze freshmen students. The plan culminates with them dumping paint on O'Bannion and him leaving in a fit of rage.
After the Emporium closes, an impromptu keg party is planned outside of town in a vacant field under one of Austin's famous "Moon towers" , attracting most of the seniors. Cynthia, Tony, and Mike arrive at their first keg party. Mike gets threatened by tough guy Clint Bruno . Afterwards, Tony runs into freshman Sabrina Davis , whom he met earlier during the hazing. Surprisingly, they begin to hang out together. Even more surprising, Dunn likes Wooderson and exchanges phone numbers with him. Mike, suffering from the humiliation of his confrontation with Clint, decides to make a stand, punches him, and gets tackled. The fight is quickly broken up by Pink and Wooderson. Football player Benny O'Donnell confronts Pink about his refusal to sign the pledge. Pink, the only player to have not signed, believes it violates his individuality and beliefs. Mitch leaves the keg party with Julie. They drive to a nearby hill overlooking town to make out. Tony gives Sabrina a ride home and they kiss good night.
As night turns to dawn, Pink, David, Don, and several friends including Ron Slater and Simone Kerr decide to smoke marijuana on the 50-yard line of the football field. The police arrive on the scene, so they ditch the drugs. Recognizing Pink, the police call football Coach Conrad . Conrad lectures Pink about hanging out with "losers" and insists that he sign the pledge. Disgusted, Pink says that he might play football, but he is not going to sign the pledge and throws the pledge into the coach's face. Pink leaves with his friends to get tickets to an Aerosmith concert. Mitch arrives home after sunrise to find that his mother has waited up for him. She decides against punishment but warns him about coming home late again. Mitch goes to his bedroom, puts on headphones and listens to "Slow Ride" by Foghat. Pink, David, Ron, and Simone travel down a highway en route to purchase Aerosmith tickets.
