"When I got the boards out of the box, more than half of them were slightly bent so they won't lay flat when used on a table. I had to bend them back. I tested them with some white board markers I had at home and they left a slight residue even when erased with a wet paper towel. I'm keeping them for use in the writing center and as quiet activities at naptime for my pre-k class. But for the price I was expecting better."