Started in 2002 by WGBH, the Teachers' Domain website brings together over 1000 free media resources from a range of public television programs such as Design Squad and Frontline. Here visitors will find both video and audio segments, Flash interactives, images, lesson plans, and student-oriented activities. This particular set of materials deals with the earth sciences, and includes over 280 different items. Each resource features details on the media type, grade level, and a brief synopsis. Some of the resources include a video about the pH of water in an abandoned coal mine, rain gardens in Kentucky, and aquatic insects. Additionally, visitors can choose to look through different subcategories, like Energy in the Earth System, Natural Resources, The Rock Cycle, and Surface Processes.