Something you should know:
Khan Academy is a great site that can help you learn just about anything and it’s free! This is especially great if you are a visual/auditory learner. There are lessons for the following subject areas: Math, Science & Economics, Computer Science, and Humanities. You can also go to Khan Academy and practice for your SAT math or GMAT.
So check out Khan Academy an excellent site to help you learn! You can also get a Khan Academy app on your Ipad, Ipod, Iphone, or smart phone!