I found the examples the article gave about students' common misconceptions interesting. I'm wondering whether the tracking and analysis by Khan Academy picks up these misconceptions as well. For example, in one of the examples (8 + 4 = _ + 5) many students answer 12 or 17. Khan Academy should be ideally placed to find such misconceptions if only because their sample size is much bigger than the average classroom.
"Khan Academy should be ideally placed..." I would say 'yes' and 'no' to this. Yes if the questions ask, and no if they don't. And that's the point of the piece. Khan won't pick up these misconceptions because he doesn't ask. He doesn't ask about decimals with different numbers of decimal places; he doesn't ask about the meaning of the equal sign. Maybe it's because he doesn't know that he needs to ask these things. That is a kind of knowledge he didn't need in his old profession and that he does in his new one. Maybe as KA grows, he will improve on this point and he will bring in people with this knowledge. But given Khan's dismissive ness of education research in the Harvard EdCast interview, I am skeptical.
