I dropped out a year or two before technically legal, 14 or 15 or something. How old are you after 9th? Last real grade I was in, though might as well not even count that since 9th and 8th were mostly suspensions and skippings.
Eventually had a girl convince me to go to adult ed, dropped out of that twice and got "expelled", but had that reversed within two weeks. Got my diploma in the end, having never been inside a high school.
I don't really regret going back, I just regret being such a sheep second time around. Sure, I bucked, but not hard since I had the whole mentality "just calm down, get your diploma and get out", which is sad because this they felt they could pull had a lot of the kids pissed, and a with a little pressure it wouldn't of been hard to start a riot and/or occupation.
I also regret not expropriating more materials. Schools are bad ass places for free supplies.