> Frequently the paper I get back is mostly blank after an hour of inactivity like this. It puts me on edge because it's so inexplicable

Have you tried finding an explanation by asking them? Don't try to appear like during an interrogation, make sure they understand you would truly like to know.

If the reason is indeed cheating in the exam, you might get a bogus answer, but chances are they are rather "cheating" (if you could at all call it that) the system. [Massimo suggested](http://academia.stackexchange.com/questions/80544#comment198727_80544) one possible explanation along that vein, another one that had come to my mind is as follows: At a university where I worked, students were allowed to take an exam a second time if they failed during their first try. So, once a student realizes they won't score a good mark during the first try, they might rather choose to fail than pass miserably and try to get a better mark during the second attempt.

> What is the best way to deal with inactive students in the testing session? Is it appropriate to demand that they leave the testing area if they're not actively working? (Students are already told in advance that they can turn in their paper and leave as soon as they're done with it.)

Based upon what you have described, no. Holding the exam sheet up in the air may be bordering on being inappropriately disturbing to others (who will, despite being focused, pick up unusual movements from the corner of the eye), but the other behaviours are simply remaining silent with a minimum of interference to other exam takers, as is appropriate while sitting in an exam room.

As a basis for your decision on how to react, try to weigh the possible advantages and disadvantages of taking action. While you may overcome your anxiety about "unnecessarily" having some more people to watch over (in particular if you can get a better idea of why that behaviour occurs), the two conceivable benefits that I see would be:

- You *might* be preventing an act of cheating. (Unlikely, as based upon your description and pointed out by others, it is not clear how a cheating technique would work in the situation described.)
- You *might* help other students who are distracted by the people in question. (Again, unlikely, given that they are virtually as silent/non-disruptive as they can be.)

The definitive disadvantage you are creating, on the other hand, is that anyone leaving the room in between - in particular when it's preceded by any form of communication when proctors ask them to leave - creates some commotion that will disturb most other students in the room.

As a final note, your question makes it sound as if some of these inactive students falling asleep were the culmination of inappropriate behaviour. Again, I'd like to ask you to check whether their sleeping actually disturbs any other exam takers. If they start snoring, sure - but otherwise, sleeping is actually a worthwhile way to spend the time while a student cannot do anything else, and at my university, we have actively recommended that activity to students in the past when for some reason they had to stay in the exam room without anything to do.