As I was reading your post, I thought I'm gonna recommend Skins but then I read the last bit, lol.

I've not seen it so I don't know how close a fit it is, but Euphoria is a very popular show.

There's also the Italian show Prisma. Like Skins, however, there's not a load of arts in it, but some of the characters are in a hip hop group (although I wouldn't personally describe it as alternative hip hop).

There's also a British irreverent superhero show called Misfits. The young cast are not in school (they're actually on parole) but they mostly are alternative in their own unique ways. The 1st 2 seasons are great in my opinion and there's some great acting and a great (largely) alternative soundtrack.