The large lecture hall is an example of something which was necessary due to past technology constraints but which persists even though it's no longer optimal. I've taught such classes of 75 to 80 students. Even at that modest size, there is considerable overhead just from managing that many people.
What we really need are uses of technology that maximize interaction between students and professors and amongst fellow students. The most productive time in terms of my teaching were the lab sessions of only 25 students each. That and office hours, which were attended by a shockingly small number of students. I suspect that study groups are also highly productive. Technology should be used to enable more interaction akin to study groups and office hours.
What we really need are uses of technology that maximize interaction between students and professors and amongst fellow students. The most productive time in terms of my teaching were the lab sessions of only 25 students each. That and office hours, which were attended by a shockingly small number of students. I suspect that study groups are also highly productive. Technology should be used to enable more interaction akin to study groups and office hours.