I agree, and I thought of that too when reading the article. In some sense, it doesn't matter if Khan is just underlining and emphasizing the same word that the

I agree, and I thought of that too when reading the article. In some sense, it doesn't matter if Khan is just underlining and emphasizing the same word that the student doesn't understand over and over again, because the goal is for the student to still have that really important interaction with the teacher where that stuff is clarified. But I think the implicit point in the article is that using Khan Academy in a school classroom is just one use case and that Khan Academy should still be useful for people who want to use it but don't have a teacher to talk to the next day about questions. And that's a difficult issue; while changing the education system is American public schools is amazing and all, the real humanitarian benefits to the site is that it can bring education to people who don't have access to other forms of education, and I have to agree that, as is, it doesn't handle that case spectacularly. I trust that it is on their minds and planned at some point, though (maybe though a better Q&A interface or something).