In a recent mission trip to Mexico, I used canvas in the chalk art classes I taught. It wasn't a sheet, but the concept was the same. We decided to use the fabric rather than the paper so that the students could use and reuse the surface. This was much lighter than trying to carry enough paper across the border to supply two 3-day workshops! When my students completed a drawing, we carried the surface outside and used a stiff bristle brush to remove the chalk. There was still a residue, especially where we had used dark colors, but a coat of white chalk took care of it.
I hope to get a chance to try out the large format sheets someday.