Brain Genie
BrainGenie is a educational website which teaches you math and science. It has many different subjects to try out. You can also create your own avatar.
You can play competitive multiplayer and try to answer questions first for points, (This is very laggy, so you need a good computer) or, play single player and get points for answering questions correctly.
You have to be 13 though, but I modified my birthdate to be allowed in. So you shouldn't have a problem after that.
BrainGenie is a very good website to hone your math and science skills. If youre looking for LA and SS you're looking in the wrong place.So if you want to be better at a certain topic, go to BrainGenie