I went to what was, at the time, the largest university in the US. My first semester, I had a biology course with more than 300 students (though the professor was awful and no more than 40 people typically came to the lectures) and a journalism class with a similar number of students that was always packed full.
After my first year, though, I probably only had 2 classes with more than 50 students, and most had fewer than 20, and we were required to interact with the professor on a daily basis --grades were given for "participation" many times, and we had to discuss any issues we were having with longer-term assignments, too.
Since I was a journalism major, I think our requirements were significantly different from my essay assignments in my science, history and English classes. We would have minimum numbers of sources/quotes, approximate length requirements, and style rules to follow. I sort of created my own specialization over the course of my education by taking editing electives and asking my professors if I could edit my classmates' assignments. It was lots of fun to take charge of my education. My friends in the hard sciences (huge, impersonal classes) and liberal arts (small upper-level classes, little career guidance) had VERY different experiences from mine and from each other.
Now, 7 years after my accelerated degree, I am going back for a law degree. They have told us our first semester's schedule will be handed out and we won't have any real choices to make, except one second- semester elective, until our second year. Weird, but nice. Supposedly, all our first-year classes are with the same small group, too.