- During the first season of the show, Mr. Rogers engages in a song with children that involves raising fingers on his hands...and ends up giving the finger on air...twice! What makes it funny though, is that he clearly realizes how it looks, and even grins to the camera. Quite possibly the only time ever where Mr. Rogers did something that could be interpreted as offensive, even if it was completely without malice or any intent to offend. Even funnier in retrospect when you consider the fact that many years later, Barney & Friends, another PBS show, used the same song involving the same type of gesture!
- In one episode, Fred visits this tuba player's apartment and offers to play the tuba himself. First, Fred took a deep breath into the mouthpiece and said "Nothing comes out." He was later instructed to blow through buzzing lips. On his second try, Fred is able to make the tuba produce sound, but it emits a funny farting noise. What makes it funnier is that the camera closes up on Fred blowing into the tuba raising his eyebrows.
- In some episode intros whenever Fred would zip up his sweater when he reached the part of the song that goes "Let's make the most of this beautiful day..." He would stretch the word "beauuuuuuuuuuuuuuuuutiful..." as he zipped his sweater. Sometimes Fred would even grin into the camera as he did so.
- King Friday XIII and Lady Elaine Fairchilde are probably the funniest Neighborhood of Make Believe characters to watch as an adult. Several examples:
- King Friday's adaptations to being a new father: in one episode, he attempts to teach Prince Tuesday (who is only two weeks old) subtraction, and at one point decrees that babies get too much attention and all babies in Make-Believe will be limited to one hour of attention per day, before Cousin Mary and Handyman Negri deduce that the King is feeling overwhelmed with the demands that having his new son puts on him, and he reconsiders when she offers to babysit.
- Lady Elaine attempting to convince King Friday to let her spy on X The Owl when he wants privacy; dressed in camouflage, she suggests he may be building bombs and training secret agents. King Friday doesn't buy it.
- When Lady Aberlin confronts Lady Elaine about her pressure on Ana Platypus, Prince Tuesday and Daniel Tiger before they start school, she responds with "I don't understand your pedagogy!"
- Lady Elaine's birthday song for King Friday in episode 1450: You're older today, You're older today, You're older than you were yesterday. You're older than I am, Much older than I am, It's your birthday, You're older today!
- Dr. Bill Platypus got King Friday good.King Friday: *Reading from a Bill of Health* "After having examined Mayor Maggie and Neighbor Aber at my tower office, I declare that they are both entitled to clean Bills of Health." [...] "Of course, touching a wheelchair could never make anybody sick, anyway, and those who think so are unfortunately superstitious." Hmph!
- In episode #1250, King Friday plays a prank on his Neighborhood subjects, with the help of Bob Brown and a large King Friday marionette. Together, they trick Lady Aberlin, Mr. McFeely, and Lady Elaine into thinking he is the real King Friday and can fly. However, the trick is spoiled when an ever-suspicious Lady Elaine discovers the marionette strings. The King's amusement is PRICELESS.
- A minor one, but during the opening of episode #1293, Mr. Rogers misbuttons his sweater. He soon realizes this, laughs at himself, and asks "Did you ever do that?".
- In episode 1353, Prince Tuesday has a squirt bottle that he's playing around with...and he squirts Lady Aberlin in the face with it, causing her to shriek and scold him for it. Darkly humorous, but there is something really downright hilarious about a normally sweet and easy-going lady get driven to such frustration in the span of a fraction of a second (don't worry, she gets better fairly quick).
- Episode 1153 starts out with Mister Rogers receiving some nursery rhyme posters he had ordered...only to find out they don't come with characters, much to his dismay. What's more though, the letter enclosed notifies him that if he wants characters on the posters, he has to send one more dollar. In one of the rare cases we see him get upset on the show, he ends up becoming a mild case of Deadpan Snarker which is really amusing considering this Mister Rogers we're talking about. As this episode was from around 1970, that "one dollar more" with inflation, would be equivalent to about six or seven dollars more today.Mister Rogers: One dollar more, nothing! (Looks at his first poster of Jack and Jill with neither of them in it) Why I expected there to be a Jack and a Jill on here. Isn't that disappointing?... One dollar more; I'm not about to send one dollar more. I have other things to do with my dollars!
- The entire last chapter of the book Dear Mister Rogers is this. After going through all the letters that ask simple questions based on childhood curiosity, the ones to help them deal with feelings, and all the heartwarming ones alongside the Tear Jerkers, the book closes with all sorts of humorous letters that you tend to expect — or not — from a child with a developing understanding of the world. One of them, for example, is from a kid who thought that the penny actually depicted Mister Rogers on the front and the trolley on the back. Another is about a kid who was dealing with upset feelings as usual, but when her mother said to beat up a pillow instead of kicking a cabinet door, her response? "Mom, you've been watching too much Mister Rogers!"
- The documentary Won't You Be My Neighbor? reveals that in one of his first public appearances after starting the show, a little boy asked how he got out of the TV. After explaining what a TV show really was, the boy followed up with "How are you going to get back in?"
- Then there was the incident where one of the crew members played a prank on him by stealing his camera when he wasn't looking, taking a picture of his exposed rear end, and then putting it back. When Mister Rogers got the film developed and saw the picture, he responded by sending a giant poster print of the prank picture back to the crew member as a Christmas present several months later.
- Later in the documentary they show a clip of Rogers singing in one of his last episodes. He opens his closet as usual to retrieve his coat and finds a stagehand hiding inside, who tells him the house has been condemned and "You've got two days to get out".
- His wife notes that several of the characters on the show are named after relatives of his. She was a bit vague whether Lady Elaine was named after his sister Elaine. The camera then cuts to Elaine, who does look remarkably like the character.
Funny / Mister Rogers' Neighborhood