While passing notes during class, Kevin asks Lisa Berlini to go to the dance with him. She says okay, but she decides to go with Brad Gaines after he asks her. While eating lunch with Winnie and Paul, Kevin feels himself falling back in love with Winnie, but she goes to the dance with Kirk McCray. Kevin tries to make Winnie jealous by dancing with an unidentified girl...
Kevin wants to take Susan Fisher to the dance, but she has a boyfriend, Donald Wallach. However, he hears rumors that they have broken up, so he's about to ask her until Donald interferes. Linda Sloan, his lab partner, suggests that they go as friends so they do. They have a good time in the beginning, but it turns sour when while Linda is dancing with Steve Padway, Kevin dances with Susan and they have punch. How is it bad? Susan leaves and Linda comes back and asks if they half-filled cup of punch that Susan left is for her, but Kevin says that it's Susan's in a not-so-nice sort of way. That basically breaks Linda's heart and she leaves. Kevin is about to ask Susan to dance again but she's dancing with Donald, so Kevin leaves, not knowing that Winnie came in, probably looking for him.
When Jack begins to complain about dry rot in the house, Kevin begins to think that his father might consider moving. When it is revealed that the Arnolds are staying put and it is the Coopers who are moving out, Kevin buys Winnie a ring as ""insurance."" Kevin decides to attend Karen's graduation from high school rather than watch Winnie leave.
News of Kevin's break-up with Winnie has spread quickly throughout Robert F Kennedy Junior High. Kevin is still in denial though and has Paul organise a party at his place so that Kevin can get Winnie alone. In an effort to make Winnie jealous, Kevin turns up with Madeline on his arm. When Kevin finally does get Winnie alone, she tells him she needs him to be her friend, but only her friend.
Kevin's quest to remain cool is shattered when Norma takes a job at his school. He tries to rebel by stealing a hallpass for Tony Barbella, but Norma catches him in the act. When Norma acknowledges him during a fire drill and the other kids laugh, Kevin decides it is time to ask his mother to stop noticing him at school.
Kevin sees Winnie for the first time since they broke up. He discovers that she a Roger have split up, too. When Winnie is in a car accident, Kevin rides over to see her at home, but her parents say she doesn't want to see him. Kevin leaves, but returns and climbs up to Winnie's bedroom window. They tell each other, ""I love you.""
As Kevin graduates from Junior High, he wants to believe nothing will change, but he learns that things can and do change when he discovers Paul is going to a private school in the coming year. Winnie is also anxious about the future. And Kevin has to drive Mrs. Heimer to the hospital when she goes into labor.
Kevin does not understand why Wayne's new girlfriend, Sandy, is with him. The tables are turned when Sandy approaches Kevin behind Wayne's back and kisses him. In fact, they kiss all over the school. But when Sandy breaks up with Wayne to be with Kevin, Kev can't bring himself to betray his brother.
Kevin doesn't want to attend his family's annual Christmas party for the neighborhood because it will only be his parent's friends - all his friends will be away. Jack is busy at work and Norma is busy at college and when several other problems crop up during the party, Norma and Jack argue. When Jack sends Kevin and Wayne to the store, they expect to return home to the worst.
The Pfeiffer and Arnold families have always been friends, but that friendship is threatened when the Pfeiffers come into a lot of money due to a real estate investment that Jack Arnold passed on. When the Arnolds are invited to the Pfeiffers country club, Jack cannot handle it. Norma saves the day with a toast to the families' continuing friendship
Kevin is motivated to get his driver's license by the promise of a date with Jessica. But Kev can't parallel park and he whimps out of taking his test and lies to his family about getting his temporary license. When Kevin tries to practice at night, he runs over the lawnmower - leading Jack to discover the truth about Kevin's license.
While Kevin is asked to consider his future, Wayne makes a decision to leave school and join the army. Jack and Norma try to talk Wayne out of it, but he won't listen. Wayne and his friend Wart go together to the army testing station. Jack follows and apologises to Wayne for not being a better father to him.
Kevin wants to date Inga and he uses Winnie to help him get a date. Winnie does the same thing to Kevin, getting set up with new guy Matt Stevens. They end up double-dating at the Spring Dance, bringing some tension to the evening. But when Matt and Inga begin to dance together, Winnie and Kevin rediscover their feelings for each other.
Kevin is on a first-name basis with McKinley's High's basketball hero, Bobby Riddle. When the team makes it to the regional finals, Kevin's dad decides to attend the game and embarrasses Kevin by talking strategy with Paul and Chuck. Later, though, Kevin apologizes to his dad for how he treated him.
Kevin, Ricky and Chuck plan on sneaking into an R-rated movie, while Paul decides he'd rather stay home and talk marine biology with a family friend's daughter. Kevin, Ricky and Chuck get thrown out of the movie theatre where "Carnal Knowledge" is playing, while Paul is at home losing his virginity. Paul confides in Kevin, but his secret gets out the next day.
When Kevin's parents go away for the weekend, he invites his friends around for a poker game. But when the game gets boring, Chuck and Ricky call all their friends and Kevin ends up throwing the mother of all parties at home - ruining the house. Norma and Jack return the next day, earlier than expected.
When Karen returns home one night, Kevin and Wayne's living arrangements are thrown into chaos. She's had a fight with Michael and they're not talking. Jack discovers that Michael had asked Karen to marry him, but she didn't want to do anything so traditional. Michael camps out on the Arnold family front lawn in the hopes of getting Karen back. Ten days later, Karen proposes to Michael herself.
Summertime used to be fun, but now everyone's gotta work. Kevin has a job at a Chinese Restaurant with Paul, but one day - after finding a Christmas card he received from Cara, decides he will visit her at the lake. Paul has no choice but to tag along because Kevin is driving. Kevin feels like recapturing the wonderful time he had last summer, but things don't go as planned.
Kevin is torn between whether to try getting back with Winnie or just enjoying his time at the diner with friends. Includes flashbacks of Winnie in the pilot, "Steady as She Goes," "Nemesis," "How I'm Spending My Summer Vacation,"" among many others. There is also a flashback to Becky Slater in "Just Between You and Me and Kirk and Paul and Carla and Becky," to Lisa Berlini in "Dance with Me" and to Madeline in "It's a Mad, Mad, Madeline World."
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.
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.
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.
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.
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.
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.
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...