[diognesofsinope]

The primary problems arise from (1) mass education and (2) cheating.

Project-based learning can't be managed with 40:1 student teacher ratios. The best learning has always come from projects and apprenticeship/mentorship style systems, but even managing that with 3 classes with a 10:1 student teacher ratio becomes hard. This should make sense, almost all the economic evidence is that parent characteristics are hands down the largest factors in what a kid's future income will be (mentorship).

Cheating is rampant which is why take-home exams rarely exist.

The reality is the world would be far better off with 3 times as many teacher, but you can't keep teachers wages as high as they are with 3 times the supply.