[[folder: The 1971 Original ]]
* AccidentalInnuendo: "Billy Lick a Lolly", especially after Molly gives a lollipop to Lilly and the song says that "Molly gave to Lilly just what Billy gave to Molly."
* EarWorm: Maybe too many to list here.
** Each time the theme song was re-vamped, it seemed to add a new ear-wormy line to the tune.
*** From the very start, there was "We're gonna turn it on! We're gonna bring you the power!"
*** In Seasons 3 and 4, they added "We're gonna open the book, and read every word we can see!"
*** And for Seasons 5 and 6, there was the new introduction, "Movin' out in a new way! Movin' out in a new way!"
** "Spider-Man, where are you comin' from? Spider-Man, nobody knows who you are!"
** "Unbutton your heart, unzip your lip, and tell me that you lo-ove me!"
** "They are the little marks that use their influence to help a sentence make more sense!"
** The Short Circus have a song called "We Love Chow", in which they put on fat suits and sing about how much fun they have overeating.
** J. Arthur Crank refers to ''Spider-Man'' as a "funny book" a number of times in the show, evidently unaware how more mature the comic would become as time progressed.
** The skit "Spidey Meets the Yeti" where a woman's demand on Spider-Man that she will stop reading his comics if he failed to stop the title Yeti became less hilarious after the negative reception of ''Spider-Man'' comics, such as ''ComicBook/TheCloneSaga'' and ''ComicBook/OneMoreDay''.
* HarsherInHindsight: ''The Adventures of Letterman'' short had a villain, the Spellbinder, whose primary mission was to wreak havoc by changing letters of words into new words, causing humorous situations ... for the most part. However, there were several episodes that, while when aired in 1974-1976 might have been seen as funny, would have such situations classed as terrorism today. These include Spellbinder changing "plane" into "plant" (by changing the "e") and causing it to fall toward the earth, and removing the "b" in bridge to create a "ridge" and a way for a high-speed passenger train to fall into the crevice; both incidents put the lives of dozens of people, including children, in jeopardy. These segments would be banned from television after Sept. 11, 2001.
** Nowadays, knowing that at least once it was Creator/MorganFreeman in the Spider-Man suit is even funnier since in the ComicBook/UltimateMarvel universe there really is a black Spider-Man.
** J. Arthur Crank, especially in the first season as an offscreen character, sounds a lot like [[WesternAnimation/FamilyGuy Peter Griffin]].
* NightmareFuel: The song "Poison" averts NeverSayDie to get its point across, then shows the Short Circus dropping to the ground and disappearing.
** One segment showed the text "thin" and "fat". "Thin" squeezes, well, thin, while "fat"...nearly overtakes the entire screen. It can be really frightening if you're not expecting it.
** The monolith cartoons scared this troper as a little kid [[https://youtu.be/zY0GhNBMkM8 scary monolith]]
** Yes, Morgan Freeman was one of the original cast members (and yes, it ''is'' weird to see him this young).
** Skip Hinnant, though it [[FunnyAneurysmMoment hurts realizing that a voice actor for an X-rated animated movie was on a kids' show]]...or [[HilariousInHindsight maybe not]].
* ValuesDissonance: The Punctuation Brothers sketch begins with three grown men entering a little girl's bedroom through her window. After they give the girl a lesson in using different punctuation marks, the girl's mother finds the men in the bedroom. Instead of calling the police, she expresses thanks to the brothers for helping the girl with her homework. It's implied that the Punctuation Brothers ''often'' break into children's houses.
[[folder: The 2009 Re Tool ]]
* CanonSue: Lisa from seasons 1 and 2. There is an entire song about how perfect she is.
* EarWorm: Some of the songs can become this.
** Three episodes in a row (the last three of Season 1) seem to give off a shared aesop of "''Never'' trust or befriend anyone who has been bad but seems to have [[HeelFaceTurn changed his ways]], since they'll always turn out to still be douches in the end."
** The episode about Lisa's colonial ancestor, who was believed to be a traitor. It looks like it's shaping up to deliver the reasonable aesop that if an ancestor or family member does wrong, it doesn't mean that ''you'' are a bad person. But nope, Lisa's ancestor is revealed to have been a hero all along, which leaves one with the impression that having an ancestor or family member who did something wrong is a ''horrible'' fate and shouldn't ever happen to a good person.
* RootingForTheEmpire: The members of the Pranksters (except for maybe Francine) are arguably much more entertaining to watch than the members of the Electric Company.
* TheyChangedItNowItSucks: Fans of the original thought a revival sounded promising, as the 1970s version used both short and long segments to deliver both knowledge and entertainment at no cost to either...but then they heard about all the changes, especially the part about using full-on stories and actually ''requiring'' the viewer to pay attention throughout. (Although to be fair to the new show, the fact they want viewers to increase their attention spans is actually a pretty noble cause.)
* VisualEffectsOfAwesome: The TitleSequence got an Emmy for this in 2011.
* WhatAnIdiot: The Pranksters. They're ''supposed'' to be evil, but their only ambition is (as stated in the pilot) to "take over the neighborhood". The town/city, fine, as at least then you've got at least one position of actual power from which you can try to bring other places under your control...but the '''neighborhood'''?!
** Francine alone has these moments a ''lot''.