From the National Park Service comes the Teachers Corner Web site on Badlands National Park. The lesson plans offered include erosion in a box, understanding rock layers, making dirt, muddying the waters, and more. Each lesson page gives a suggested grade range, key concepts, background, materials, procedure, results, and a why section that explains the scientific reasons behind the results. The pages are simple and easy to follow while containing good material that should help kids learn about geology and our national parks.