Not too long ago, one of the pre-school kids asked one of my 7th grade students if she would help her get something from "The Lady of the Stickers" [me]. The junior high has their classes in the same part of the building as the pre-school. One of the little girls from the home is in the pre-school class, and she used to wander into my room occasionally after school. I have a bunch of stickers in my desk and would always give her one when she came.
This got a little bigger than I had intended. Pretty soon I had mobs of four-year-olds knocking on my door to ask for stickers while I was giving classes. I've taught them to wait until they see my door open, though that doesn't stop them from constantly peeking into my room on tip-toe to see what's going on.
I'm not sure why, but they always put them on their foreheads. Some days they forget, but most days during recess I get a small group of them, larger if they decide to announce it. The other day I just closing the door when from the top of the play slide, Angela glimpsed my open classroom door, pointed her arm like she was charging into battle, and yelled, "STICKERS!!!" That day took awhile.