Clay

Clay can satisfy the deep-seated need for children to play in and with their natural environment. In an unrestricted outdoor setting, children are drawn to dig and build, using earth and water and get messy. Clay is a way of providing this kind of experience more regularly. It can be set up indoors, so it can be available on rainy days, and it is available to those with no rough outside space for digging. - excerpt from Earthen Treasures by Shelley Hancock