The show centers on a group of kids who get by pretty well with minimal input from adults, and the stories offer themes of problem-solving and cooperation. Helga's bullying behavior causes some of her peers to cower around her, and the fact that her actions are meant to hide her crush on Arnold doesn't make them forgivable. Mild gross-out humor like squished worms and crusty scabs.
Cartoon-style accidents (crashes and collisions) that sometimes lead to broken bones and scratches, as well as some punching that's meant for comedy.
A girl harbors a secret crush on a boy, often admitting in secret that she loves him.
No cursing, but kids say things like "I hate you," "freakin'," and "crap," and there's some name-calling like "dork" and "geek."