I have been using white clay the past two days with my 7th grade groups and find a dust has settled over absolutely everything. I did the same clay unit in the fall and didn't have nearly this amount of dust. When I went out of my room for lunch, I could see the tracks down the hallway...and when I made it back to my desk at the end of the day, my computers and EVERYTHING is just covered...could it be a different kind of clay. How do I stop the madness? without going mad!