| Abstract: | This lesson about the theory of plate tectonics begins with a description of the chemical and physical layers of the Earth featuring text and scientific illustrations. It then discusses the historical development of the plate tectonic theory, and concludes with descriptions of the locations and types of plate boundaries. Students will learn the three layers of the Earth, observations that support continental drift and sea-floor spreading, and the basic concepts of plate tectonics. Students will be able to describe the ways that plates move, relative to each other. They will also learn that the plates move on the softer, convecting mantle called the asthenosphere, and that plate margins are identified by the distribution of earthquakes and volcanoes. This lesson also allows the student to examine the steps in proving a major theory. In addition to the lesson, there is a list of references about plate tectonics, a link to an extensive web site on volcanoes, and a list of activities and teaching suggestions for plate tectonics. |