How do I convince my parents to let me go to art school?

I'm in my 2nd semester of the 10th grade and I can honestly say that I'm finished with school. Before I found out there was even an art college I wasn't going to go to college at all. Now I'm stoked. The art college's criteria for admission is 1) A High School Diploma or the equivalent 2) Write an essay on why what you would learn at the school would be helpful to your future career. Well I'm not too keen on finishing high school and I just want to go to the art school. So I'm guessing the equivalent of the HS Diploma would be a GED. How do I sit down and talk to them about this? By the way I am 16.