When my daughter took the course a few years ago, she said her class divided into four groups:
Front few rows: ultra nerdy private school kids who took careful notes on everything the teacher said.
Next couple of rows: nerdy public shools kids who sort of paid attention, but not diligently.
Third set of rows: non-nerdy kids of all flavors who paid little attention and played hangman, or texted each other, or read a book, or whatever.
Last set of rows: stoners who were quite obviously high/asleep for most of the classes.