Dynamic Earth is an interactive Web site where students can learn about the structure of the Earth, the movements of tectonic plates, and the forces that create mountains, valleys, volcanoes, and earthquakes. It consists of four sections, a glossary and an assessment. Each section explores one aspect of the Earth's structure and the movement of its tectonic plates. At various points of the interactive, students can check their knowledge by taking a quick quiz or playing a game to see how much they have learned. Dynamic Earth includes an extensive assessment section designed to evaluate how well students have learned the content and skills. Educational levels: Middle school