Every teacher has heard the words, "I lost my pencil" or "I need a pencil." The system that I use in my room is, "Need a pencil? Leave your shoe!" Students trade in their shoe for one of my pencils. I enjoy this system because then you aren't interrupted in the middle of teaching to the sound of the pencil sharpener or the dreaded pencil questions. The students help themselves and return it when they are finished.