On career day, an inventor who is treated poorly by the Sweathogs offers a well-paying job to Gabe.

Freddie, class treasurer, is accused of stealing funds, and an impromptue trial is held in the classroom.

The Sweathogs form a gang, but won't let Arnold in until the night of their first rumble, and Arnold, against the idea of being killed, brings along Gabe and Mr. Woodman in order to prevent the fight.

Sparked by the fact that Vinnie neglected to do Freddie's homework, the Sweathogs spend the better part of class fighting with one another.

Mr. Kotter takes the sweathogs on a field trip to a museum. Mrs. Kotter and Mr. Woodman are along as chaperones. They meet the unusual museum curator Mr.Gore (John Astin) who seems odd and superstitious. In the Egyptian display, he warns them of the mummy coming back to life if they joke and kid around. Naturally, the door shuts itself and everyone is trapped. They humorously begin to panic and make attempts to get out. Epstein manages to get the door open.

Gabe is afraid to get a physical when the free clinic comes to Buchanan High.

Julie's visiting sister, recently at odds with her long-time boyfriend, falls for Juan.

A girl wants to ask Vinnie to the Sadie Hawkins Day dance, but his insensitivity leads her to ask Arnold in retaliation, leaving Vinnie with no date at all.

The new student teacher discovers that all her training to work with remedial children hasn't prepared her for dealing with the Sweathogs.

When the opportunity to fight Carvelli in a boxing match arises, Arnold wants to be the one to do it; and when the other Sweathogs put down his manhood, he is even more determined to prove himself by getting in the ring.

Epstein is caught smoking cigarettes. Gabe and the sweathogs try to get him to stop.

At Christmas time, the Sweathogs are all too eager to tease resident bum Angie. But after Angie tells his life story to the class, they have a change of heart, and decide to help him get back up on his feet.

When Juan's sister Carmen joines the Sweathogs, she catches the eye of Arnold, but Carmen is only interested in Vinnie. Juan, meanwhile, is displeased with the entire situation, and is ready to kill anybody who dares to lay a hand on his baby sister.

Vinnie's goofing off in gym gets him in trouble with the teacher, Mr. Caruso, who's reprimending after class gets out of hand when he hits Vinnie in front of the girls' locker room.

Tired of the way the school newspaper is always putting them down, the Sweathogs join the staff in order to redeem themselves; and the crack investigative team of ""Vinstein"" (Vinnie and Juan) are hot on the trail of the culprit behind the recent break-in of Principal Lazarus's office.

Gabe's overly-critical father comes for a visit and, unconvinced that his son has chosen a worthwhile career, goes with Gabe to school in order to watch him in action with his Sweathogs.

Gabe, in need of money for a root canal, takes a second job as a restaurant mascot.

When Arnold finally shows back up at school, it's discovered that his absence was due to the recent death of his fifth father. A feeling of responsibility within him, Arnold sets out to find a job to help support his siblings and his mother, who's only priority lies in finding a replacement father for her kids.

Gabe and Julie find out that they are going to have a baby.

It seems that Freddie has a future in radio, but he may also risk losing his friends for fame.

With Gabe away at a teacher's convention, the Sweathogs take it upon themselves to watch over the pregnant Julie...but the harder they try to make Julie comfortable, the more trouble they seem to cause.

The art teacher falls in love with Gabe.