I live in Iowa and have taken several classes with the iowacconline.org program and I love them! They are set up in a way that is pretty easy to follow and understand. For the most part they are not self paced but you have a discussion and assignments to turn in each week. I didn't take chemistry online, but I did take A&P I and II online. I do kind of think by taking science classes online you don't get the full, hands on experience because you do simulated labs, but overall if you can't take it in class I think it is worth it.