If you and your students are recycling in the classroom, checkout Jinjerup's cheerful recycling labels. Just print on adhesive paper, cut on the dotted lines, stick, et voila!
These labels could also be printed and laminated for a sorting activity. Students can organize images of items by which bin each one should be disposed in. Older students could cut out magazine pictures to represent the things that should be dumped in each bin.
Image from Jinjerup.