And I have to say, I agree with Khan and Bill Gates, constructivism might be hypothetically true, but it is not applied in school at all. In fact, when I had math homework, the word problems that were supposed to tie mathematical concepts to the real world were the things that I and all the other students hated most. There were some comments to the news article, complaining about how drilling problems does not teach kids why the subject is important, or how being able to do calculus does not mean one actually understanding what a derivative is. That is true, but it is not limited to the Khan Foundation. It is prevalent throughout schools, where none of the teachers ever explained why derivatives were important, or what they actually were, and only taught how to find them (and even that was poorly done). So at the very least, Khan's approach is a dramatic improvement over what the schools are doing, since at least he does drill, and kids do learn how to solve problems.

The rest will have to be up to teachers, since there are things that can only be taught through real person to person interaction.