Season 2 Plot Summaries Go to Episodes for original air dates
1) "Out of Retirement." Mr. Wilson gets a visit from his former boss from Pittsburgh, who offers him back his old job. When Dennis thinks Mr. Wilson is moving to Pittsburgh, he runs away from home.
2) "Dennis and the Wedding." Mr. Wilson's niece (Elinore Donahue, "Father Knows Best") is getting married and asks Dennis to be the ring-bearer.
3) "Dennis and the Radio Set." Mr. Wilson gives Dennis an old radio set that he accidentally bid on at an auction. However, when Dennis finds money in the set, Mr. Wilson gets excited.
4) "Dennis and the Ham-Pher." Dennis gets what he thinks is a hamster, but it turns out to be a gopher that escapes from its cage and almost ruins Mr. Wilson's yard.
5) "The Stock Certificate." Dennis switches Mr. Wilson's old phone book with a new one without knowing that there was something hidden in the old book.
6) "Man of the House." Dennis tries to take care of his sick mother while his father is out of town.
7) "The Rock Collection." Dennis starts a rock collection and ends up finding what he thinks is real gold on Mr. Wilson's lot.
8) "Henry and Togetherness." Mr. Wilson tricks Henry out of playing golf so that he'll spend more time with Dennis. Meanwhile, Dennis and Tommy (Billy Booth) try to deal with a hole Dennis put in the fish tank.
9) "Paint-up, Clean-up Week." Dennis wants to help out during Paint-up, Clean-up Week, so Mr. Wilson gives him a bucket of red paint for his wagon . . . and the wagon isn't all that gets painted.
10) "Dennis Learns to Whistle." Dennis is very upset because he doesn't know how to whistle, so he spends all day trying to learn.
11) "The Raffle Ticket." Mr. Wilson is conducting a car raffle for his lodge and Dennis wants to win the car for his mother, so he buys a ticket from Mr. Wilson that has the number his Ouija board recommends.
12) "The Christmas Horse." Determined to get a horse for Christmas, Dennis searches the neighborhood trying to find what he thinks is his horse.
13) "Dennis' Allowance." Dennis asks Henry for an allowance of 25 cents per week. Henry says he'll give it to him with the condition that he learns the value of money first by earning it himself.
14) "Dennis' Penny Collection." Mr. Wilson helps Dennis start a penny collection, although he fears that the collection is going to be trouble for himself.
15) "Dennis, the Campaign Manager." Dennis convinces Mr. Wilson to run for park commissioner so that he'll open the park all week long instead of just on the weekend.
16) "Miss Cathcart's Friend." Dennis wants to find Miss Cathcart (Mary Wickes) a best friend, so he gets her a dog from the pound.
17) "Pythias Was a Piker." Dennis has to write a composition for school about his best friend, and he chooses Mr. Wilson.
18) "Dennis and the Saxophone." Dennis wants Henry to buy Tommy's old saxophone for him, but when Mr. Wilson finds out, he tries to talk Henry out of it.
19) "Wilson Sleeps Over." Dennis accidentally knocks over a bottle that fumigates the Wilsons' house, leaving them no other choice but to stay the night with the Mitchells.
20) "Dennis' Birthday." Mr. Wilson puts on a magic show for Dennis' birthday and asks Spring Byington to be his assistant.
21) "Dennis Goes to Camp." Mr. Wilson takes Dennis and his friends to a day camp and ends up stranded there for a week after a storm takes out a bridge.
22) "Dennis' Tool Chest." Miss Cathcart's cat is accidentally locked in the trunk of Mr. Wilson's car.
23) "The Going Away Gift." Dennis gets Alice a going-away present and hides it on Mr. Wilson's closet shelf. Mrs. Wilson finds it and thinks it's a gift for her.
24) "Dennis and the Fishing Rod." Dennis wants to buy a fishing rod for Henry and tries to purchase it with a Confederate bill.
25) "Dennis and the Good Example." Dennis decides he wants a bird, but he knows that he won't get it once his dad sees his report card.
26) "Dennis' Obligation." Dennis brings home chicken eggs to take care of as part of a school project, but he ends up taking them over to the Wilson's house because of a power outage at the Mitchells'.
27) "The Dog Trainer." Dennis trains Mr. Wilson's dog, Fremont, but the training backfires when Fremont will only listen to Dennis and ignores Mr. Wilson.
28) ""Woodman, Spare That Tree." When Mr. Wilson drops a hundred-dollar bill, only to later find it sitting in an old tree, he decides to climb the tree himself to retrieve the bill.
29) "The Boy Wonder." Mr. Wilson builds a barbecue in his backyard with help from Dennis' friend Fred Baines (Skip Torgerson).
30) "The Soapbox Derby." Dennis enters a soapbox derby, and Mr. Wilson accidentally ends up being the one driving Dennis' car in the race.
31) "Dennis and the Camera." Mr. Wilson is supposed to take a picture of a plant that blooms at night but ends up dozing off when the time comes. Luckily, Dennis takes a picture of the flower for him.
32) "Dennis and the Miracle Plant Food." When Dennis accidentally steps on one of Mr. Wilson's plants, he buys a replacement and plants it in the flower bed without Mr. Wilson knowing.
33) "Dennis' Newspaper." Dennis overhears Mr. Wilson saying that he wishes he had his raccoon coat back. Dennis gives the story to the newspaper, and as a result people bring Mr. Wilson raccoon coats.
34) "Mr. Wilson's Paradise." Mr. Wilson wants to go to the Island of Happiness in Mexico but changes his mind when he hears that his niece is going to have a baby.
35) "The Fortune Cookie." Mr. Wilson gets a fortune cookie that reads "Beware of tomorrow" and is convinced that the fortune will come true.
36) "The Pioneers." Dennis, Henry and Mr. Wilson camp out to prove to Mr. Krinke (Charles Seel) that they can live off the land like pioneers.
37) "Father's Day for Mr. Wilson." Dennis decides to give Mr. Wilson his own Father's Day, and it's a special day indeed when Dennis helps him out of a lawsuit involving his dog Fremont.
38) Dennis and the Picnic." Henry finds a bag of money in the gutter and calls Mr. Wilson to witness his discovery. They take it to the police station but later learn that the money is counterfeit.