[capnrefsmmat]

> A video can't do this. But perhaps 2 hours of video + 1 hour of interaction might be just as good as the 2 hours of lecture + 1 hour of interaction provided by the current system. If so we can cut our teaching expenses by 2/3.

Okay, but that doesn't improve education, it just makes it cheaper. It would certainly be a useful start; one could invest that money in hiring better-qualified teachers, or even a program where college students come in to do interactive tutoring.

> This is a big problem - the US spent $864B on government-sponsored education in 2009, more than it spent on the military.

How much of this is personnel and salary costs for teachers?