I am looking into some alternatives to playdough in my daycare to give the children a different learning experience and I have heard mixed reviews on Moon Sand. It's supposed to be sand that is kind of sticky and you can mould into different shapes without using water. Some people claim they love it and others hated it, claiming it was really messy and not worth the money. Has anyone had any experience with this product? If so, what did you think? Pros/cons? Would you buy it again?