My point was that a large 500 person lecture on "Intro to ElectroMagnetism" will be about the same as a small 20 person lecture in terms of material. The varia

My point was that a large 500 person lecture on "Intro to ElectroMagnetism" will be about the same as a small 20 person lecture in terms of material. The variability will come from - Honors sessions - Extra seminars - Quality of Material - Quality of student support groups All of these things get better as the class size grows. In my last class at Georgia Tech, there were 900 students studying a niche topic from a particular professor. Due to class size, there were ~12 TAs and an extremely active slack discussion group where people could get support. A smaller class just means the professor has limited resources to assist students.