Honestly if you have a strong vision and a plan with what you are planning to do. You don't need school. I've met plenty of young CEO's 19-20 who have dropped out and are doing well (ie. Gumroad CEO, USC drop out). But the difference between the successful ones from the ones you see bumming around is that they have a vision and plan with what they are about to pursue.
edit: If your actually planning to drop out to pursue something (brand, company, etc) I hope your a well spoken person (ie. strong speaker, and strong writing skills). It's a common trait you see from those who are successful (again referring to CEO's who have dropped out). You don't need to piggyback on a degree to get far, but being a strong and well spoken person will get you far in life.
What you don't realize, is that most people like that come from pretty well off families, and have the credit to borrow loans and shit to start a company. Banks and private lending companies really aren't giving loans out like they used to.
I'm not sure the OP is living that life lol, especially since he wants to be a dancer.
I honestly think that at his current state, by dropping out he is just dooming himself to a life of dead end jobs.
I don't know for sure though, I'm not gonna lie i'm not the expert. My whole family is college educated, all the way to my aunts, uncles, and cousins, and I grew up in an area where pretty much everyone goes to college, gets a degree, and gets an internship or goes to grad school and usually ends up pretty well for themselves.
That's all I really know, and everyone I know that did dropout or didn't go to college is like a bartender or works on cars (The car thing is oddly a common trend around here for people who didn't go to college, I even know a couple guys who own their own business so kudos to them)
but Dancing? idk man, all the REAL dancers I know went to good snooty art schools, or just quit dance altogether and got a non creative degree.