* Whenever Bossun makes his embarrassed face (or any other similar expression). Made funnier when it's shown that even [[spoiler:his blood-related brother]] Tsubaki and his sister Rumi [[spoiler:not blood-related]] make that exact face!
* J-son sensei's attempts on his marriage interview are hilarious with his nervous actions playing out like a horror movie.
* Whenever Prof. Yamanobe appears and introduces any kind of weird games to the Sket Dan, to the extent that they get way too invested into them, be it Genesis, Hyperion, and many others.
* Chuuma's concoctions are practically a recipe for humor (and disaster):
** Bossun's expressions getting mixed up.
** The entire shenanigan with the invibility potion. It even breaks Switch's usual stoic face. Then he goes on an extended rant afterwards.
* During the process of the series, it's unbelievable that Tsubaki can be incredibly too clueless, [[DitzyGenius very gullible]], and spaced out. Admittingly, he is way too HotBlooded when it is about his duty as the vice-president and president of the Student Council... but, ''seriously'':
** When he is dressed up as a girl, alongside Bossun and Switch (Katou is anime only, though) for the first time just to make Usami more comfortable around men... he is just acting way too reserved or distant while the others act a little bit more in character.
** His lack of fashion sense when he comes up with the designs of his own T-shirts.
** He doesn't know about common known technologies such as videogames (until Bossun invites him to try one) to what is an USB (confusing it with a pencil lead, for god's sake).
** He is so easy to fool (especially when he loses his contact lenses and confuses the Sket Dan with the Student Council).
** How about being targeted by 30 or so gun-wielding mafia (while Katou was practically all over him to deflect the bullets) and he doesn't even notice anything strange.
* Everything that is related to [[MisplacedKindergartenTeacher Remi]] and the mishaps that occur as a result of her ditziness.
** Her family is even more clumsy than her (with exception of her brother) too!
** Special mention is that some of the incidents caused by Chuuma's experiments are even her fault.
* Episode 38 ("Costume Break") is a hilarious story of the Sket Dan trying to escape the warehouse they're trapped in, with moments including:
** Bosspecter's epic face when he realizes they are trapped in the warehouse.
** The crew [[OutOfTheInferno emerging from the burning shed]] in a creepily hilarious way looking like zombies in their burnt costumes.
* Himeko trying her hardest to ask Bossun out on a date in episode 43, and acting shocked when it actually ''works''.
* Samurai and Pudding's RealLife meet-up, starting from Switch's schemed set-up. Having the two completely look right past each other up until their [[CringeComedy awkwardly shocked/embarassed]] faces at the realization of just who they've emailing the entire time is hilarious. Then they start acting out the usual scenario.
* The whole School Trip Rhapsody arc (kicked off by Bossun and Himeko going through a FreakyFridayFlip thanks to Chuuma's concoctions), and the whole shenanigans that happened in there:
** Switch trying to keep an eye on Saaya [[spoiler: because she was going to confess her love to Bossun]], but people keep distracting him from his objective. They even confuse his intentions while doing so, as if he was a StalkerWithACrush.
** All the awkward moments that Himeko and Bossun have to pass during the whole trip, including but not limited to helping each other change their respective clothes, going to the toilet, and washing their respective bodies... how they went through that? They had to use ''blindfolds''. It's like they were expecting the worst of the situation, but it also raised some eyebrows from their classmates.
** In the bus, Tsubaki ends up being hypnotized to believe that he was Bossun. He tries to break it and gets [[DitzyGenius distracted by a CAT]]. He ends up acting as one during the whole arc.
* Bossun gets addicted to a game that his mum Akane also used to be hooked on. Rumi calls Tsubaki over to snap him out of it -- only for ''[[NotSoAboveItAll Tsubaki too]]'' to get addicted. The problem is resolved... by getting Akane to join in the game and beat them up to get their attention. Rumi is understandably crept out by all three's obsession with the game (and their equally uncreative weapon-naming sense).
* Agata's thinking about the whole LoveDodecahedron theory about his sister, Saaya. Instead of getting the part that "Saaya is in love with Bossun" (he never thought of that, of course), he concludes that she was actually in love with Tsubaki.
** The Sket Dan (along with Saaya and Shinba) devices a complex scenario to clear up the misunderstandings so Agata could focus on his second entrance exams, only to make things worse. Thankfully, he managed to clear it before going for his exam [[CrowningMomentofAwesome and even managed to get a perfect score]].
* After losing the 2nd Character Popularity Contest, Bossun is forced to spend the entire Chapter 165 as a stickman. The other characters' reaction to all this is hilarious, to say the least.