This DVD on earth contains four 20 minute programs. Titles included are: "Forces Shaping the Earth," "Plate Tectonics," "Volcanoes and Earthquakes," and "Weathering and Soils." Also included on the DVD is a teacher's guide and student activities. The PDF guides for each program can be accessed by putting the DVD into your computer and opening them via Adobe Acrobat Reader on both Macs and PCs.