I recently made some sensorial touch boards for Z
The first one is a rough and smooth board. I had found a rectangular piece of plywood at a craft store a few months ago and decided to use that. I stuck sandpaper on one half of the board but couldn't leave the other side as is since it was grainy , so I used what I had on hand and first stuck brown paper and then contact paper
The second board comprises of alternating rough and smooth strips. I had the carpenter cut out a piece of laminated chipboard to the same measurement as the plywood piece used before, then stuck 4 strips of the same grade of sandpaper at equal distances
The third board has 4 strips of sandpaper and they vary in gradation so that it's roughest at the top and smoothest at the bottom.