Does anyone have a good clean up plan? My biggest issue is with 6th and 7th grade and the state they leave my sink and paint brushes in. My classroom sink is right outside my classroom, so it is hard to monitor both what is happening outside at the sink and in the room. It never fails, someone (no one will own up to it) leaves a pile of unclean pallettes and ruined paintbrushes in the sink. I have tried limiting the sink to two at a time, but then we get a long line of people waiting and clean up takes forever and there is still a mess. Any thing that has worked for others?