* In "One Stayed Clean." If you watch closely this episode parodies SavingPrivateRyan with Gus' friends sacrificing themselves so that he will remain clean for picture day. Really. Replace words like playground with country and kindergarteners with enemy soldiers. Gus' friends' devotion and resolve to keep him clean shows how loyal they are. What really nails the tear-jerker moment in, when its only Gus and T.J. in a hole as their last means of sanctuary and shelter, is Randall playing Red River Valley on a harmonica as T.J. strengthens his resolve to protect Gus. :'(
* This piece of FridgeLogic (Or FridgeHorror): Because Gus has to move from town-to-town all the time (his dad's in the military), he's eventually going to leave [[CityWithNoName the town the show is set in]], and leave the best friends he's had ''in his life''. It's ''heartbreaking'' when you think about it.
* Although they're (usually) antagonists, Ashley A. getting kicked out of the Ashleys in "Outcast Ashley" is sad in a way. These girls have been friends since preschool, and were kicking out their best friend ''just for forgetting to wear purple on the anniversary of the day they met''. She might've done some bad things in the past (and in future episodes, as this was one of the early season two episodes), but you can't help but feel sorta bad for Ashley A. The part where they ''rip her 'A' necklace off and stomp on it'', and then tear the head off her teddy bear backpack, is especially harsh.
* "Speedy, We Hardly Knew Ye". The gang return after the weekend to see that the class hamster, Speedy, has died, and get all the kids to have a funeral for Speedy. Later, the high school football team, the bus driver, and even the mayor arrive at the funeral, because ''they'' also had Speedy as their class pet. It's then revealed that every time Speedy dies, he (and in some cases, she) is replaced with a new hamster without anyone knowing. Everyone's upset because they realize that the Speedy who just died wasn't the Speedy they remember, so T.J. gives them a speech on how it doesn't matter which Speedy belonged to who; it was that Speedy was always a great friend to them.
* Gelman's bullying towards Gus in "Gus's Last Stand". Especially hard for someone who's been bullied heavily.
* Spinelli getting bullied endlessly in "Mama's Girl" after accidentally calling Miss Grotke "mama". It starts out somewhat humorous, but it gets to the point where she's afraid to go to school because of the bullying.
** And Miss Grotke's speech about how bullying can really hurt someone, though the tears that flow will be of the "Amen to that" variety (if such a thing exists).
* In "More Like Gretchen", after Spinelli's parents compare Spinelli to Gretchen and inadvertently make the latter feel inferior, she becomes so angry that she tells Gretchen that they're no longer friends. And Gretchen didn't even know what she was doing wrong--she was just being herself.
* In "Weekend at Muriel's", we have [[JerkWithAHeartOfGold Ms. Finster's]] reaction to overhearing Spinelli call her "boring".
-->'''Ms. Finster''' (''looking at a picture of herself in her youth'') Is it true, Muriel? [[JerkassWoobie Have you really gotten...boring?]]
* Just the thought of what would have happened had the gang been split up after the breaking of that statue in "Biggest Trouble Ever". Spinelli and Vince would have let their more negative traits get the best of them without TJ to balance them out, Gretchen would have skipped out elementary, middle and maybe even high school and had ''no'' friends and Mikey and Gus might not even have survived until high school. Only TJ would have made it out okay... and that's almost worse!
* The way Ms. Finster reacts to Principal Prickly's promotion in "Prickly is Leaving" is very sad to watch. Especially when she tells the main six that she refuses to do anything that might disuade him from leaving because she cares about him and wants him to be happy.
* Mikey discovering that Ms. Salimony is engaged in "The Voice" after developing feelings toward her is very sad to watch. The poor kid almost gave up singing after this.
** At the end of the episode he sings "Nobody Knows the Troubles I've Seen" while gazing longingly at Ms. Salimony. It's hard to watch the scene without shedding a tear.
* "Pharaoh Bob" is this when you think about it. King Bob becomes a bit shaken at the fact he'll be forgotten after he stops being King of the Playground so he forces the students to build a pyramid (and becoming a jerk in the process). After said pyramid is destroyed by the rain (due to it being made out of mud and not stone), he's confronted by Gretchen and laments how he simply wants to be remembered and not forgotten.
* In the episode, "The Hypnotist", this applies to Principal Prickly bonding with T.J. and the Recess Gang. T.J. promises that Prickly, who preferred to go by the alias of "Petey" as he was [[ItsaLongStory hypnotized by accident and made to believe he was 6 years old]], would always have friends as long as they were around. Prickly then went to go play on the swings, only for Vince to point out the problem with T.J.'s statement: [[CaptainObvious Prickly is not a child, he only believes he is]]. Second problem: because Prickly was no longer of sound mind, that would've made Ms. Finster the new principal in charge. They had to return Petey back to his old self, and as a result, lose their new friend.
** When they try to break the bad news to Petey that he's not really a kid, [[IRejectYourReality he refuses to believe it, screaming the whole time that he's not a grown man, insisting over and over he's a kid]] as Gretchen releases his mind from the hold the hypnosis had over him.
* The whole of "Bonky Fever" is sad. Mikey is turning ten, and his mom (who's apparently walked him to the bus stop and waited with him ''every day'') tells him that now that he's getting older, he'll be going on his own. Mikey spirals into a deep depression that he copes with by reminiscing about Bonky, a [[LawyerFriendlyCameo singing, dancing dragon designed for preschoolers]]. His friends watch in horror as Mikey regresses further and further to a childlike state: he plays with Bonky toys made for little kids, carries around a hand puppet that he treats as a living thing, starts speaking like a baby, and even asks T.J. to help him to the bathroom. The final straw comes when his tenth birthday party is Bonky themed, with all of the kindergarteners attending, and Bonky "himself" appearing in a suit. The gang is forced to reveal the person in the costume--it's Mrs. Blumberg, who was trying to give her son what he wanted. Mikey runs out of the house, and she pursues him; this leads to one of the most earnest, frank, and generally heartbreaking conversations about growing up ever recorded on kids' TV. Mikey confesses that he ''knew'' his obsession with Bonky was childish, but was so afraid of losing his mother and drifting away from her that he tried to recapture his lost youth. Mrs. Blumberg then admits that their bond will never quite be the same, but promises that she'll always be in his heart. The entire thing is a bittersweet meditation on getting older, how [[ParentsAsPeople our parents are human beings, too]], and that childhood is something that inevitably ''has'' to end.
** The final shots of the episode pack in even more Tear Jerker moments. Mikey walks to the bus by himself, takes a deep breath, and climbs aboard, sitting next to Gus...and then the camera pans to reveal Mrs. Blumberg hiding behind a tree, where she was watching her little boy in case he needed her. The episode ends with her clearly choking back tears as she walks away.
** It takes on meta-levels of sadness when the original audience of the series--now in their twenties and early thirties, and perhaps even with children themselves--watches the episode through YouTube; a peek at the comments reveals a lot of people sharing Mikey's desire to go back to a simpler time...
* In a similar vein to the above, the episode "The Legend of Big Kid" ends on a surprisingly sad note. T.J. is ambushed and captured by the kindergarteners, and over time, he gradually regresses into one of them. While his friends do rescue him in the end, T.J. admits that there was something wonderful about remembering the joys of being an innocent, carefree child, unafraid to nap or finger paint however he wanted. Gretchen points out that every kindergartener will eventually grow up, which is treated as a fate to be mourned, rather than celebrated. Like "Bonky Fever," it becomes particularly poignant upon watching again as an adult.