It is really cool that Sal is trying to do everything himself, but this method does not scale. There is no way he can create the breadth, and more importantly,

It is really cool that Sal is trying to do everything himself, but this method does not scale. There is no way he can create the breadth, and more importantly, the depth, needed to cover all the topics a student will learn. As long as Sal continues to produce all the content himself, I believe the Khan Academy will be relegated to complementary and supplementary content.