"Do you have problems with Subs who don't follow your plans and have kids do
"whatever" they want in your classes."
I avoid having students work on projects when I am gone, and use my sub days to work from the textbook and/or watch an art history video (which I preview and write up a question sheet for). If I plan far enough ahead I can book the computer lab and have them do an art history webquest. I think most of my students know and could follow the procedures well enough to manage project work, but it only takes a few lazy ones to trash your room. The only exception to this is my AP students, who can work on whatever they need.