I was exactly the same way. I studied for AP tests on my own time, started a company, learned how to program, etc. School was boring. It was easy. I resented the fact that my peers took it like a joke an weren't serious about learning -- some of the teachers did, too.
All that was cool, but here's the thing I wish I did the most in high school: kissed a girl.
I think it's important to get good grades in HS because it will give you so many options when you graduate. Just deal with it. Some times you have to do stuff you don't like.
The rest of the time spend doing the things you love. And as a fellow introvert, I strongly encourage you to SOCIALIZE. I had a friend who forced himself to become less awkward by joining the HS football team even though he hated football. Forced socialization.
It worked. He was way less awkward than me in HS. Now he's in Boston doing this: http://diybio.org