It comes but twice a year, here at the university: Quiet Day. It’s the day after the classes end but before finals begin.
I’d like to think of Quiet Day as a sacred time of mystical contemplation. The reality is that, since I don’t teach or study, it’s really just another day at work for me. But the campus is noticeably quieter today.
I don’t know how many universities observe such a day. At many schools, finals week corresponds to an actual calendar week, so it is always buffered from the last day of classes by the weekend. At Indiana University people called the last week of classes Dead Week, during which no homework should be assigned or tests administered. I suspect that this was more of an informal convention, perhaps just a campus legend, rather than an official policy. But I note that some universities, at least, really do observe a Dead Week.