Major English Texts II cheating scandal
The 2013 Major English Texts II cheating scandal involved a lot—a lot—of people cheating on a "notoriously easy" English class at Barnard College. Basically, two things were happening: (1) people were cheating on weekly reading quizzes with Google and (2) students were paying other students to go easy on those student graded quizzes. And it turned out that most of the cheaters were Columbia College students.
Of course, it doesn't help that the instructor, Peggy Ellsberg, let students self-grade the quizzes.