[andrewce]

This seems like it could be really useful when paired with "The Gutenberg Method" (http://entropysite.oxy.edu/morrison.html), which basically asks students to do the assigned reading at home, along with some type of annotation of "Here's what to look for".

Then, in class the next day, the teacher answers any questions, briefly covers any difficult concepts, and they can spend the rest of the class-time engaging with each other instead of lecturing.

My suspicion (disclaimer: I was, at one point, a teacher) is that if you want people to use this service, you'll have to show how it improves instruction, and you'll have to do so in much more concrete terms than you have here.

That said, if I ever have a classroom of my own again, I can see myself using this tool when appropriate.