Theo and Cockroach plan a party at Cockroach's house, and they plan to only invite girls. Rudy sees a snake in the basement, and Clair is terrified because ever since Cliff teased her with a plastic snake when they were young, she can't stand snakes. Cliff and Clair trap the snake in their bedroom and throw it out.
The family helps Denise prepare to leave for college. Rudy is nervous now that she's going to have her own room, but Vanessa can't wait to be alone. Clair questions Cliff's love of junk food and challenges him to eat healthy foods for one full day. Cliff tells Theo to bring him leftovers from Cockroach's house because the healthy food is so boring. The family offers a bittersweet farewell to Denise as she leaves for Hillman.
The Huxtables prepare for Russell and Anna's 50th anniversary party. Denise rides home with Sondra and Elvin from college and has to endure them bickering the entire time. Elvin insults the Huxtable women with his sexist comments and turns to Cliff for advice. The Huxtables take Russell and Anna to see the Count Basie Orchestra.
Theo becomes attracted to a new girl, which threatens his relationship with Tanya. Cliff refuses to give Theo advice after the many difficulties he had with Sondra and Denise. Clair tells Theo that he will date a lot of girls as he grows up and that he should be honest with Tanya. Theo invites Tanya over, and she tells him that she is interested in another boy; because of this, they decide to break up.
Rudy puts makeup on Cliff that she found in Vanessa's purse. Clair reminds Vanessa that she is not allowed to wear makeup until she is 15. Vanessa wears some to school anyways and gets caught by Clair, who punishes her. Theo studies fire safety at school and organizes a fire drill at home; all goes well until the family ends up locked out of the house.
Theo is excited about the coming weekend because he has no homework or studying to do. He is discouraged when he receives a 'C' on a history paper that he is forced to rewrite over the weekend.
Theo and Cockroach want to become pilots after a member of the Tuskegee Airmen gives a speech at their school. Cliff and Clair allow Theo to take a flying lesson, and Theo realizes that getting his pilot license takes a lot of time and money. Rudy brings her new boyfriend Kenny home and bosses him around the whole time. Cliff tells Kenny to stand up for himself.
Theo teaches Rudy how to play checkers and is upset when she beats him. Vanessa invites two popular girls over to impress them so they will invite her to be on the school's pep squad.
Denise and Sondra come home for the weekend to keep Clair company while she nurses a back injury. Denise gets a 'D' on a third straight English assignment, and the professor allows her to redo it.
Rudy wants to keep a dog that she and Peter found. Cliff allows them to look after the dog until they find the owner. Rudy is sad when the owner shows up but does not want a pet of her own because it is too much work.
Russell invites some friends over to the Huxtables' for pinochle, and the men share war stories. Cliff tries to tell his Navy stories, but the men ignore him because he served during peace time. Vanessa prepares for a skating date with Tyrone but is smitten when Sgt. Stokes' grandson Aaron shows up at the house. Tyrone invites Aaron to the skating rink, much to Vanessa's delight.
Clair is offered a position on a committee to plan a celebration honoring Hillman's retiring president and will be gone for 10 days. Anna goes with Clair so she can see Denise, and Russell stays to help Cliff with the kids. Theo is caught by his principal covering a note about himself in the girl's bathroom. Rudy and Kenny get into an argument because Kenny says sexist things he learned from his older brother.
Sondra and Elvin come for a visit, and the family is shocked to see that they barely argue anymore. Elvin gives Theo some pointers for his upcoming wrestling match and confides to Theo that he and Sondra are talking about marriage. With Vanessa's help, Rudy writes a letter to Clair at Hillman.
Rudy spends the night at her grandparent's house but does not want to stay. Russell and Anna cheer her up by playing dress-up and showing her old family photographs. Denise takes Vanessa with her for a night in Greenwich Village. Cliff and Theo plan to spend a "man's night" together after a girl Theo likes doesn't call him, but the girl shows up at the house and Cliff persuades Theo to take her out.
Cliff and Theo go to a auto dealership to replace their station wagon. Cliff dresses down so as not appear that he is a doctor, but one of patients recognizes him; the dealer gives him a good deal on a new car regardless. Vanessa helps Rudy with a project by telling her to add photographs, leading Rudy to cut pictures out of Cliff's encyclopedias.
Denise is home for the weekend and is excited about a blind date with a guy she has been talking to for a few months. Vanessa's ex-boyfriend Robert comes to the house and seeks love advice from Cliff and Theo, as he has suffered a string of break-ups and misses Vanessa. Vanessa tells him that they are better off as friends.
Cliff fills in at the hospital for another doctor and finds that three women are set to deliver around the same time. Vanessa gets upset at her friend Althea because she smokes cigarettes in Vanessa's room.
Theo and Rudy play "circus" in Theo's room, and Rudy slams into a wall and hurts her face. Cliff says she is fine, but Clair wants her to see a pediatrician. Cliff is upset that Mrs. Granger, a nice woman who works at the hospital, is being laid off due to cutbacks. Cliff tries to intervene on her behalf, but Mrs. Granger takes her layoff well and tells Cliff she is going back to college on her daughter's dime.
Denise throws a bridal shower for her friend Veronica and finds out that Veronica is pregnant. Veronica tells her that she got pregnant so that her parents would allow her to marry her boyfriend. To keep the boys out of the house, Clair tells Cliff and Theo to install some new shelves in the office. Vanessa takes Rudy and Kenny to the skating rink.
The Huxtable kids throw a lunch party for Cliff's 50th birthday. They get him a keychain that beeps when you clap, but Cliff is the only who can't get it to work. Cliff invites some friends over that evening for a party, and Clair is upset to see that he invited Mark, someone who was once married to one of her good friends but cheated on her. Mark and Clair have a long talk, and Mark begs for Clair's forgiveness.
Theo sends away for a practical joke set and plays pranks on everyone in the family except Cliff, who says he will never be tricked. While Cliff is at the hospital, Sondra and Elvin show up and announce that they are getting engaged.
Cliff catches the flu from Clair, and both are laid up in bed. Theo takes control of the house and makes Vanessa and Rudy do all of the work. Vanessa and Rudy complain to their parents, and Clair takes charge again. Cliff is so sick that he babbles incoherent stories to Theo, who tries to trick Cliff into agreeing to buy him a sport's car.
Cliff is excited to see an old Navy buddy but is shocked to learn that he suffered a heart attack and needed a quadruple bypass. Cockroach wants he and Theo to shave their heads so they can appear in a music video. Cockroach goes through with it but regrets it when so many people show up for the auditions and only 12 are selected.
Cliff takes Rudy and some of her friends to a nice restaurant for lunch and is bemused when they don't want anything on the fancy menu. Clair's sister Sarah stops by to visit Clair, and they are amused by Vanessa's stories of Theo trying to teach her how to play tennis.
The Huxtables go to Hillman to attend a ceremony honoring Dr. Hanes, the retiring university president. Dr. Hanes asks Cliff to be the master of ceremonies, and Clair sings a song with the school choir in his honor. Dr. Hanes gives an eloquent speech to the audience.