A great article on Schema Theory:  http://www.compasselc.com/play-builds-brain/   Members be sure to go to our Member's Only section for items posted from the last workshop, there are charts on Schema Theory to dowload! 

A great website and recipe for sensory / natural playdough!  I will have parents sign up to make the basic dough monthly and then divide it and add ingredients.  https://www.cooksmarts.com/articles/homemade-scented-play-dough-recipes/