Online classes are awesome. I'm doing brit lit online right now, need to finish by the end of the year to get credit and that's more than enough time, especially considering all the tests (except for the final exam) are done online, you have unlimited time and they actually tell you can look back at the lesson material. So there's no reason to not get everything right on the tests. Only downside is that it costs $100+ for each class, which can be hard for most highschool students to pay for on their own (though have friends in college who say that's nothing for an entire class).
Totes great because you can fit other stuff into your schedule or not take that class at your highschool because you get the exact same credit for it as you would in school.