One of my favorite learning websites is Khan Academy. www.khanacademy.org. If you can't find it, google "khan academy," and then you will find it. Often when I put in the web address, I get switched to something else.
Learning for free for everyone with a computer with math, science and economics, computer science, humanities, and test prep. If Khan Academy is new to you, be sure to look around at everything for an overview. The knowledge map is interesting. Under science and economics, you can learn everything from cosmology and astronomy to macroeconomics. Under test prep, you can study for the GMAT.
There are over 4100 videos that are interactive and measure progress for the student wanting to learn. Khan Academy is an excellent tool in the classroom or at home for young and old.
I haven't visited this website in months but in looking around, I see that it is organized differently. At first I thought many videos were cut out but I see that they are still there. Have fun. Look around. Learn.