Early in this movie Cady is given a drawing of the lunch room where each stereotype sits. They are hilarious:
Girls who eat their feelings
Girls who don't eat anything
Unfriendly black hotties
Sexually active band geeks
The greatest people you will ever meet (Art Freaks)
The worst people who will ever meet (The Plastics)
Hahahaha, I am not saying that these are true but I am saying that people fall into multiple categories in high school because I certainly did.