You do need one tutor for each student, though. While students can tutor each other in some cases and while being a tutor can be a great learning experience itself, one-on-one tutoring is hard to scale in many educational contexts. Hence the persistence of large classes, and hence the continued search for technological solutions.

Not quite, in my limited experience, just one hour tutoring per week makes a huge difference. If this generalizes well we could have more of a 1 to 30 ratio.