Penelope once asked Kathy to prove if she is a girl.

Cartoon violence is extreme. People are hit in the head with anything available (computers, chairs, baseballs etc.). It also has a running gag, pratfall, falling, hitting objects, get into a fight etc. Although they later seen mild injuries.

There is one episode that involves a boy who rhymes a lot (see quotes) almost says "ass." Some people may miss it.