So basically this:

One girl is nerdy. One girl is shy.

One girl is popular and girly, and the other loves boyish stuff and is basically a tomboy.

The shy girl the next day literally becomes a different person after standing up to her bullies. I don't know, she wears leather jackets, wears her hair down, puts on lace-up boots, and probably plays electric guitar while listening to punk music.

One likes sports, and the other wears pants.

And then there's the popular bitch and the rebel!

By saying that your cleverness, lack of makeup, strong mind, independence, and so on forth makes you different from other "girls/guys", it's implied that your gender is inferior by default. The implication of femininity isn't bad, it's more like the culture's idea of proper femininity is bad. (This is where I got the idea and words from: tvtropes.org)

Doesn't this trope annoy you all? Like, when people don't know how to write it good...

Literally all the girly teens in one group, and then there's the one girl that is quote in quote "odd."

"That girl is so odd! Wearing a hoodie and men's boots!"

"I'm NoT LiKE oTHer gIrLs"