These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Harsher in Hindsight Episodes dealing with Wheels' drinking problem are much harder to watch nowadays. Neil Hope, the actor who played him, had a drinking problem for years, which may or may not have played a role in his death.
Never Live It Down (Michelle is absolutely infamous for crying - which she does about 3 times in the whole series, once at her parents divorcing, and twice at her boyfriend cheating then dumping her. Apart from those, she was actually one of the more proactive characters in the series)
Tessa told the other kids the school was burning down. She dated Alex of all people and even Yick. But it always comes back to the fact that Joey Jeremiah fucked her.
The Degrassi parents don't like the idea of Christine being in school with their children after she gets pregnant
Derek killing a child while drunk driving.
No Yay (Michelle's father's actions always came off as a little... unfatherly)
The Scrappy (Kathleen and Claude, though both are definitely meant to be unpleasant)
Tearjerker: After everyone finds out that school bully Dwayne has HIV he admits "I used to like it when people were afraid of me but this is different."
Values Dissonance (Many of the story arcs, especially Michelle's and Dwayne's, only make sense with early 1990s attitudes toward parenting, AIDS, and so on; also, modern audiences will probably not be amused by the scene where Joey and Wheels dance as caricatured Mexicans)
Unnecessary Makeover: Stephanie gives one to herself. She was actually pretty without the makeup set to whore.
Wangst (Claude is king here, but it's left deliberately unclear whether you're supposed to sympathize with him)