It's my understanding too that the home team sets the time. I find it odd that some teams opt to play at 6 or 6:30 pm when they've played at 7 or 7:30 pm all season. Seems to throw off the rhythm.
I don't think much consideration is given to the AP tests and such. You can always take it at a later time. All the spring sports have to deal with the testing issues.
