so kids like sixth grader alex hernandez can take as much time as they need to learn a concept. >> alext to school in mexico. some things she can explain to me, but some, like, she can't. so, like, i take long to, like, try to finish my homework. >> gupta: how did you used to do in math? >> hernandez: pretty bad. like, at a third-grade level math. so, you know, khan academy has helped me. it's like... it's, like, opened doors that i couldn't open. it's helped me a lot. >> gupta: a lot of people have talked about the idea that flipping the classroom is... is sort of what's happening here. you take a little bit of issue with that. >> khan: i kind of view that as... as a step in the direction. the ideal direction is using something like khan academy for every student to work at their own pace, to master concepts before moving on. and then, the teacher, using khan academy as a tool, so that you can have a room of 20 or 30 kids all working on different things, but you can still kind of administrate that chaos. >> gupta: khan academy has created a dashboard so teachers like courtney cadwell c