The story of Kevin Arnold facing the trials and tribulations of youth while growing up during the 1960s and 70s. Told through narration from an adult Kevin, Kevin faces the difficulties of maintaining relationships and friendships on his enthralling journey into adulthood.
While Kevin tries to take his relationship with Winnie another step, Wayne's friend Wart returns from Vietnam a changed man. Kevin decides to steal the opposing team's mascot at the homecoming football game, but the childish prank is overshadowed by a realization of how Wart has been affected by the war.
It looks like the father-son fishing trips might come to an end when the lastest outing is plagued with problems.
When the Arnolds attend the wedding of Jack's boss' daughter, one of the bridesmaids turns her attention to Kevin. He tries to get a bottle of champagne for them to consume together, but ends up drinking it while he waits for her. When she does arrive, Kevin vomits on her. Later, Wayne tells Kevin that he's had sex with the bride.
Kevin wants to earn some money to take Winnie out for dinner, so he jumps at the opportunity to paint his sociology teacher's house. When he tries to con some younger students into helping him out, things start to go wrong.
Kevin gets jealous of a charismatic political campaigner who has encouraged Winnie to help him out.
Some people never find true love, but Kevin believes he did. He had what most people search all their lives for, but he blew it. When Winnie comes over for a study session while his parents were away, Kevin wants to relationship to go further. Winnie sees through his plan. She does stay, but they just fall asleep together. The next day, though, he tells his friends a different story. When Winnie finds out, she dumps him.
Wayne has fallen head-over-heels for Bonnie, a 23-year-old divorcee who has a child. Norma and Wayne fight about him wanting to move in with her. Kevin, meanwhile, is feeling lonely and wants desperately to talk with Winnie - to apologize and because he realizes he really needs her.
It's another day of work for Kevin, who keeps calling Winnie when he can - even though he keeps getting in trouble with Mr. Chan because of it. Kevin also feels he is in competition with the pizza delivery guy.
While Kevin and Winnie are concerned about their futures, Jack gets a disappointing evaluation from his employers at NORCOM. Kevin doesn't want to end up in a job like his dad has and Jack is getting pretty tired of it, too.
It's Christmas and the Arnolds have a lot to celebrate. Things begin to unravel though, when Kevin thinks Winnie has bought him an expensive present and he wants to do the same in return. And Jack's new business gets into trouble when his partner, Charlie, decides to drop out and return to NORCOM.
Wayne seems to be a changed man, considering his relationship with Bonnie and her baby. Kevin longs for a romantic vacation with Winnie, but must face reality on New Years Eve when Bonnie leaves Wayne for her ex-husband.
When Kevin is offered a great deal on a used car from Alice's dad, Pistol Pete, Kevin has to decide whether to betray his friend, Chuck, who has broken up with Alice again.
Kevin wants a story that he and Winnie can tell their kids. So, when he is grounded after receiving a speeding ticket, he sneaks out of the house anyway. Kevin, Winnie and friends are off to see The Rolling Stones, who are rumored to be playing at Joe's place, which is out of town. But when they arrive, Joe says he doesn't know who the Rolling Stones are.
Kevin's new friend, Jeff, was the first kid he ever knew whose parents were divorced. Winnie has Kevin set Jeff up with Ann, but Jeff is feeling guilty about the girlfriend he moved away from. Ann is upset that Jeff doesn't want anything to do with her and Winnie blames Kevin! To sort everything out, Kevin drives Jeff to talk it all over with Julie.
Kevin discovers that he's pretty good at wrestling. He thinks about giving up until he realizes that Winnie likes him being an athlete. The coach even talks Kevin into going into competition.
When Kevin and friends are asked to write down the ways they feel inferior, they have trouble thinking of something. They don't have any problems picking on the new girl with the big nose. Ricky decides to ask her to an upcoming dance anyway, but all his friends laugh at him - none of them realising how insensitive they are being.
On the way to the Planetarium, Kevin and Winnie and Alice and Chuck play ""Truth or Dare."" When Winnie asks Kevin what he'd change about her, he thinks and then says sometimes she is just too perfect. She doesn't appreciate this and tries to prove that she make trouble as well as anyone else.
Over a game of poker we learn some truths about Kevin's friends, including that Chuck thinks he's gotten Alice pregnant, that Randy is worried about failing trigonometry and that Paul and Kevin are drifting apart.
Kevin and his dad don't know what to do about the women in their lives. First, Winnie has out-scored Kevin in the SATs and is thinking of applying to Harvard and Princeton. Second, Norma has gotten a job as a financial supervisor, leaving Jack to think she'll neglect her household duties. When the two Arnold men realize that the women in their lives are upset at their attitudes, Kevin takes Winnie to the bowling alley to apologise, only to find his dad has done the same thing for Norma.
The Arnolds fly across country so Norma can attend her 25-year class reunion. Her parents keep talking about her old boyfriend, Roger, which upsets Kevin, but not Jack. Kevin realizes that the bond between his parents is stronger than he realized.
It is summer and Kevin is working for his dad in the furniture factory. He is getting frustrated and wants to take off with Jeff and Chuck on a road-trip, but he can't. Winnie, what's more, is working away from town and Kevin wants to visit her - so he quits his job and leaves town. When he gets there though, he finds that he is not wanted and that Winnie has fallen for a lifeguard named Eric.
After Kevin loses all his money and his car in a poker game, he decides he has to leave the resort - there's nothing to keep him there now. The next day he says goodbye to Winnie, punches Eric and storms out. Hitchhiking out of town, he runs into Winnie who has been fired from her job. They begin to argue and lose the ride they had flagged down. Later, sheltering in a barn they talk about how much has changed between them. Winnie thinks it's just inevitable - that everyone grows up. Kevin doesn't want to believe it and neither does Winnie, not really. They kiss, passionately. The next day they both return to Kevin's hometown for the last 4th of July he will ever spend there. Karen has returned home and she is pregnant...