I have a scotch thermal laminator and I buy the laminate pockets (mostly 5 mil, sometimes 3 mil) to make "boards" for various math games. I've been using dry erase fine point markers for my students so they can mark the board while playing and then erase for the next game. Overall .. it is staining the boards... and it's sort of difficult to wipe off. I was surprised to see this.. I just assumed it would wipe off like dry erase does on my marker board. Is there a different kind of marker I can use so my kids don't need to spend 5 minutes and some serious elbow grease to get the games clean? I thought I could just switch to glossy plastic sheet protectors.. but they are so flimsy. Thoughts??