Joe,
One of the things I have done/permitted/allowed: I put a "time limit" on tests in regards to when I would like to start class up again. I make sure students know, however, that if there are students who need more time, I can put the unfinished exam in the Testing Center we have, and at their earliest opportunity they can go in and finish. It helps to keep the class moving if you have the exam at the beginning part of class.
Can there be drawbacks from this? I know there could be. The students who need the extra time, though, have usually been the more academically honest students, at least the ones I have dealt with in this regard.
I don't know if this will be of any help or not. If nothing more, it's at least a suggestion.
