I teach a sewing class ay my house every Sat am. I use bed risers under a folding table to raise it for cutting and it works wonderfully. We do the same thing at retreats. The weight of the table keeps them in place, if concerned you could glue rubber matting to the bottom of the risers, but I have not done this and mine sit on ceramic tile with no problems at all. Go for it! Your back will thank you!
Michelle