I did that yesterday. Took a test at 9 am, was done by 9:30 am, waited around for my 11 am class only to be told "Yeah, we're not doing class today, go home." ... waited around for my 12:30 pm class and sat in it for 20 minutes before he said "Today sucks, go home."
I should have brought my laptop yesterday.
.... right now, I'm eating something so I can take pain meds for my evil cramps of doom. Thankfully, I don't have class on Fridays.