Free Classroom of the world
The Khan Academy is a not-for-profit 501(c)(3) with the mission of providing a world-class education to anyone, anywhere.
Khan Academy, with Khan as the only teacher, appears on YouTube and elsewhere and is by any measure the most popular educational site on the web. Khan's playlist of 1,630 tutorials (at last count) are now seen an average of 70,000 times a day -- nearly double the student body at Harvard and Stanford combined. Since he began his tutorials in late 2006, Khan Academy has received 18 million page views worldwide, including from the Gates progeny. Most page views come from the U.S., followed by Canada, England, Australia, and India. In any given month, Khan says, he's reached about 200,000 students. "There's no reason it shouldn't be 20 million."
Check it out now..