Six-part interdisciplinary teaching packet. Through the story of the 1980 eruption of Mount St. Helens, students will answer fundamental questions about volcanoes. By learning about volcanoes, students will understand that the Earth comprises interacting components, or subsystems: the geosphere and the biosphere. In turn, the geosphere comprises the lithosphere, the atmosphere, the hydrosphere, and the cryosphere. These lessons show how the eruption of Mount St. Helens affected all of the Earth's subsystems.