Cory tells Mary Beth that his girlfriend's name is Topanga, to which she replies, "That sounds like a freeway exit." That is how Topanga got her name. Jacobs needed a name, and they were passing Topanga Canyon, and it stuck.
The boom mic can be seen at the top of the screen when Erik is in the Dean's office and stand up.
Rider Strong (Shawn Hunter) can be seen with an earring in his upper left ear. It remains for only a handful of episodes as the earring can't be taken out for a few months until it heals. It is removed for filming by the start of season 5.