If you can't convince your parents to let you unschool, or even to homeschool you, finishing high school online might be a decent intermediate option for you. It's more "school-like" than homeschooling and unschooling, so in theory it should be easier to convince them to let you do it.
Depending on where in the world you live, it may either be easy or hard, or free or cost money. In the US, many online high schools are state-sponsored, meaning they're completely free alternatives to physically going to class. Not all are free, though, but a lot are. You also get private online schools and charter online schools.
So how do you convince your parents to let you finish high school online?
Tell them it's just like regular school, except you don't have to physically go there. You'll get a perfectly normal high school diploma when you're done. You still have teachers who give you work to do, but you can do it at your own pace and you don't have to deal with annoying classmates, bullies or anyone else you don't want to see. The downside is you won't see friends at school either, but you can still see them after school.
You can also tell them that because you work through it at your own pace, you'll learn "valuable time-management skills". This is just a fancy way of saying that you need to be able to motivate yourself to do the work... which can be a downside as well since it's the same regular boring schoolwork you've been doing since forever.
They might bring up the socialization argument and say that you'll become a hermit or something, to which you can respond by directing them to this article (well, print it first if you don't want them to actually visit this site). Basically, if you're not forced to be around obnoxious people, you'll be LESS likely to become a hermit.
We have more info about finishing high school online here. There are also links to more articles and sites where you can get free online classes on just about any subject. And here's a list of online high schools in the US.Resources by SoulRiser on January 13, 2010 @ 3:25 PM