Prelims at Cornell are a beast somewhere between a test and a final. We generally have two or three of them in each class during the course of the semester. Mostly, we take them at night, not during class time.

Prelims tend to come in bunches, so there are about 3 weeks of Hell scattered throughout the semester, 4 weeks if you count finals. The administration likes to schedule my prelims for the exact same time, forcing me to reschedule them and take two in a row.