It's an old Over Head Projector (OHP) that we use for our light table. It has provided hours of learning - exploration in light and shadow, color combinations (using the transparent color blocks) as well as lessons in cooperation. The children have been "repairing" it with tape, winding it round and round. The top part of the OHP broke off so they needed to repair it with tape. (It now has a plastic top, after the glass broke). Experiences in collaborative repairing.