Wally gets a job at the ice cream parlor leaving a gaggle of girls swooning and Eddie and Lumpy feeling neglected. So to get back at him, Eddie and Lumpy concoct a plan of revenge that involves Mary Ellen Roger's slumber party.

Wally's school is having an exchange dance and Wally and Eddie must take girls from a rival school that they chose out of a hat. Eddie asks to trade with Wally and he agrees, like a shot, after seeing the picture of Eddie's intended in a yearbook. Suspicious, Wally soon quickly discovers why Eddie wanted to trade; the girl is a few inches taller than Wally.

Beaver and his friends are all psyched to go on a camping trip with Gilbert's father as an escort. However, when Gilbert's father suddenly has to work and everyone is down in the dumps that is until Wally agrees to take them. Meanwhile, Eddie and Lumpy decide to secretly tag along and scare the boys with animal noises.

Wally is rounding up some guys to go to an amusement park and he's one short from getting a discount so he settles on Beaver. However, Beaver begins having second thoughts when he hears stories about one of the rollercoasters.

For $25, Wally buys a car and signs a contract with the owner knowing full well what he's getting, a car that doesn't start. Wally quickly finds himself with more trouble then he bargained for when the lemon becomes a fixture in front of the Cleaver home.

When Beaver and Gilbert are pretending to go for a drive in Ward's car, Beaver accidentally releases the parking brake, causing the car to roll down the driveway and into the street, backing up traffic. Wally steps in and drives the car back in the driveway and clears up the traffic mess, but he soon finds himself being issued a citation for driving without a license.

Ward allows his car to be driven by Lumpy who must get Eddie, Wally and Beaver to a sporting event in a neighboring town. However, on the way back, Lumpy disobeys Ward's orders and takes a shortcut home.

Angry with his dad for taking his car keys away, Lumpy Rutherford decides to secretly join the Merchant Marine Corp and has the enlistment information sent to the Cleaver's address instead of his own. Trying to be a good friend, Wally hides the Corp literature in his room; but, when June finds it while cleaning, she's sure that a break-up with his girlfriend and a recent reprimand from Ward have made Wally unhappy enough to leave home.

Wally finds himself smack dab in the middle of a lover's quarrel when a woman tries to make her estranged boyfriend jealous by continually making tennis dates with Wally. Wally finds himself in an awkward position when the boyfriend threatens him.

June, Ward and Wally are going out for the evening and not wanting to worry about Beaver, June calls a babysitter, despite Beaver's pleas against the idea.

Eddie pompously announces that he's dropping out of school to get a high paying job at a gas station. However, all is not as it seems when Wally and Lumpy get a glance at Eddie's new free spending life.

Beaver has Gilbert over to spend the night but after they watch a gangster movie things get out of hand. A suspicious car has just pulled up to the front of the house with two strange characters sitting inside, and they just happen to be Lumpy and Bill, dressed for a masquerade party. Not knowing this, Beaver calls the police and Lumpy and Bill are arrested.

Wally and Beaver reluctantly give up their Saturday morning to clean the yard, miss the garbage man's pick-up deadline and go from the frying pan into the fire when they trust Eddie Haskell and Lumpy Rutherford to take the trash to the dump in Lumpy's car.

Beaver and Wally become interested in the stock market and Ward decides that they should try their hand at it. However, Wally and Beaver have different ideas about what to invest in compared to Ward who wants them to play it safe and invest in Mayfield Power and Electric, while they want to invest in a more risky venture.

The Cleavers are all excited about their annual summer vacation up to the cabin, that is except Wally. Wanting to be close to his latest girl, Wally wants to stay behind and gets permission to stay at Eddie's house during the two weeks the Cleavers are on vacation, but June and Ward are a bit unsure of Wally's plans.

Ward and June find themselves in the dark when they hear through the grapevine that not only is Wally going steady with Evelyn Boothby but that wedding bells may be heard soon. Meanwhile, Wally gets a different picture of marital life through Evelyn's sister and her husband.

Wally and a bunch of other guys are invited to spend the weekend at Scott's cottage on the lake. However, the one thing that could keep Wally from going, Scott just happens to forget to mention, that there will be no parent supervision.

Beaver has been having trouble in English and Ward persuades Wally to tutor him. Wally has Beaver look over an old exam that he once took and to Beaver's surprise, the next day, his teacher gives him the exact same test, which he of course he aces. However, Beaver is left with a guilty conscience.

Wally plans on going to a big dance with Evelyn Boothby and they plan on getting there cramped with six other people in Lumpy's car. When June and Ward refuse to allow that, Wally and Evelyn must find another way to get there. However, what Evelyn has in mind doesn't go over well with Wally.

Beaver learns a girl he fights with is leaving town.

Beaver agrees to help Richard cart his family's clothes down to the laundromat, however, half way there they discover that Richard has lost the three dollars his mother gave him. This leads him to ask Beaver if he could use the Cleaver washer. They soon find themselves in another jam when the washing machine overflows after Beaver put in too much soap and starch.

Beaver and his friends decide to make a call to California to talk to Don Drysdale and they agree to chip in on the cost of the call, assuming that it's only going to be a couple dollars. However, when they're put on hold, the cost quickly jumps up to $9.00.

Beaver has told his parents that he doesn't want anything big for his birthday and they decide to respect his wishes and give him a gift of money. Beaver also gets quite a bit of money from other relatives and finds himself debating on whether or not to spend it or put in the bank, like his parents suggest.

During a particularly awful golf game, Ward happens to break his driver and decides it's not worth repairing it, so he just puts it in the closet. Later, Gilbert talks Beaver into hitting around some golf balls with Ward's clubs and one hit with the broken driver has Beaver thinking he broke it.

A communication gap ensues when Wally wants to spend the night at Lumpy's and Beaver wants to have Gilbert spend the night. Beaver asks June and she tells him, he can sometime when Wally spends the night somewhere and Wally asks Ward, who tells him he can sometime when Beaver has someone spend the night.