I have shared this before, but let me share it again!! Did you know that Crayola will collect your dry markers? They 'Color Cycle' it. It's so easy you start a collection for dry markers. I have a separate container for the caps... I'm sure I'll find something to use them for :) You box up your collection, weigh it, and print out a mailing slip to attach to the top of the box. The instructions say leave it for your Fed Ex person to come to your school and they will pick it up for you. SOOOOOO easy!
My students and I have recently collected 30 lbs of dry markers. They are right now in the office ready to be picked up and my students are helping to reduce, reuse, and recycle.