Fonzie's Falcons and their rival gang, the War Mongers, attempt to settle their old scores with a game of softball. The outcome is disputed, so they end up rumbling. Marion confronts Howard about his anxiety over becomming a grandfather, and Chachi continues to try to make up with Joanie.

Al tells Chachi about his dull, mundane life, so Chachi suggests that he ask his mother out. He shows up at Arnold's the next night disheveled and tells Chachi that his mother is already seeing someone. Chachi is shocked and vows to get to the bottom of it.

Chachi tells Joanie that he wants to date other girls and soon realizes that he's made a big mistake. He tries to straighten things out with her, but she goes out on a dinner date with another guy.

Lori Beth asks Fonzie to be her coach in a new birthing method called natural childbirth. He's fully on board until he learns he has to be in the delivery room with her.

Fonzie and Roger are dating the same girl but don't know it. Meanwhile, Joanie is upset that she and Chachi don't go out as much as they used to, and Howard and Marion argue about love letters he wrote to her.

Fonzie substitutes for Roger in his hygiene class, and, as a prank, the students hide the lesson plan and tell Fonzie they're learning about sex. Roger is later informed that he will be fired as a teacher as a result of Fonzie's teachings.

In order for Jenny to join the Rondells, a popular club, she has to steal a statue from Pfister Park and bring it to their clubhouse. Joanie is there to help, and they are both caught by Officer Kirk.

Fonzie is rejected several times by a new teacher at Jefferson High. After he kisses her in a final attempt to win her over, she screams and runs out of the house. Roger talks to her and finds out that she is a nun.

Joanie takes care of Richie Jr. for the weekend while Lori Beth visits Richie in Greenland, Howard and Marion go to New York on business, and Fonzie is away at a teacher's convention. Jenny invites several people over for a party against Joanie's wishes. On top of that, the boiler breaks down.

Dateless for an upcomming concert, Jenny is set up with Eugene Belvin by Joanie and Chachi. They, along with Fonzie, try to make Eugene appeal to Jenny by making him seem more manly.

Joanie has to decide where she wants to go to college: UCLA or the local UWM. She wants to go to UCLA, but Howard very much wants her to go to UWM, even offering her a new car as incentive. After much deliberation, Joanie announces that she's not going to college at all.

After seeing reports on television, Al feels compelled to visit the South to take part in an upcoming freedom march. Fonzie, concerned for his friend's well-being, decides to go with him.

Meanwhile, the Cunningham's television set is broken, and, while it is away being repaired, Howard suffers withdrawal symptoms.

Fonzie and Chachi's grandmother becomes very upset at them for suggesting that she move into a retirement home after they observe some signs of senility.

Al is chosen to head the Leopard Lodge's annual Poobah Doo Dah when he says he can get his distant cousin, Frankie Avalon, to perform. However, as Al is auditioning other acts to round out the show, Avalon calls to say he can't make it.

Initially furious that the music teacher, Cynthia Brannigan, hires the Boston Conservatory Orchestra for the annual Jefferson High concert, Fonzie changes his tune when he realizes that famous composer Tchaikovsky was very much like himself. Fonzie decides to get the entire Jefferson High gang to like classical music.

The gang tries to get the Lone Ranger, Fonzie's idol, to appear at his birthday party. Meanwhile, Fonzie thinks about becomming a one-woman man.

Roger seeks Fonzie's advice regarding his love life, Joanie and Chachi write a song for their band, Potsie tries to get into the Leopard Lodge, and Marion is the lead in her theater group's musical.

Roger's family sends his brother, Flip, to Milwaukee with the hope that Roger can straighten him out. Roger entrusts Flip to pick up Marion after he attends a Fats Domino concert, but he skips the concert to hang out with some hoodlums and leaves Marion to walk home in the cold.

After a day of fishing with Howard, Chachi gets to thinking about his future when he realizes that being a success in the music business is a long shot. He leaves the house determined not to come back until he finds a career that would be sufficient to support Joanie should they get married one day. He tries his luck at being a salesman.

Jealous of Joanie's friendship with a new girl in school, Mikki, Jenny spreads a false rumor that Mikki is pregnant. As the rumor circulates, Fonzie is added to it as being the child's father.

After a month of dating, Al wants to ask Chachi's mom to marry him. Being an old fashioned guy, Al asks Chachi's permission. He grants it but doesn't think she'll want to marry Al.