I recently gave information about Khan Academy, but now that I have looked at it further, I have to comment again... IT IS THAT GOOD!
Khan Academy delivers math and finance tutorials through Youtube videos. It is well detailed and my kids say it is very easy to follow. In addition to that, they have a free, adaptive math program available here. I can't believe this is free. I spent 2 hours on the site today, just testing myself and could not stop. The site finds your level and fills your learning gaps. Plus it progresses you through math seamlessly.
I plan to use this program this year AND make a few donations!
Another update 9/24/09
My kids have been using and enjoying this program for 3 months. Because of the way the program moves students can fly through concepts too quickly. This means they may be able to finish a unit but have not spent enough time in it to rememeber the concepts long term.
My suggestion is that you purchase a workbooks... basic math, pre algebra, algebra 2, geometry to go along with the lessons so give them extra practice and to test for long term retention. (You can also print worksheets from free worksheet websites)
Otherwise this program is excellent especially for test prep and relearning concepts.
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