Also one hundred papers to grade, and a few dozen thank-you notes to write. Plus letters of recommendation. Plus lots of e-mails to answer from parents who need status updates. Right away. To keep abreast of any developments over vacation.
This is why man invented Facebook breaks and Scrabble moves. Also, the cozy spot in the house.
Alternatively, one could be spending the Day after Christmas navigating the parking lot at the mall.