It's common practice for teachers to number their tests. That way it's easy for me to see if I've gotten all of the tests back. I usually fan them out so I can insert each test into its proper spot in the number order as students turn their tests in. So, when the last student turns in his/her test, the tests are already in order.
The trick is to get the kids to figure out what I'm up to, so instead of just putting the test on top of the pile, they file the tests in themselves. And since the room is (supposed to be) silent, the idea is to get them to figure it out without my explaining.
I've done this sort of thing before.
Usually, the kids figure it out and start putting their tests in the right order. But today I was dealing with 8th graders. They didn't get it. I had maybe five students catch on. Five students...all day.
It didn't matter how I had the tests lined up. Every student put his/her test on top of the thing. I even had one kid who took my fanned out system and "neatened" it into one stacked pile. Ugh!
Of course, I had other things to worry about. I had one student actually whisper to a neighbor, "What is the answer to number three?" Seriously.
In total I caught two cheaters and two students who were acting suspiciously. So, the day wasn't a total loss.