Explore how environmental conditions and changes have had a profound effect on history. These classroom-ready activities show students how to apply the principles of earth science to events that have dictated America's past and present, from 30,000 years ago to today. Such historical events as early migrations to and from North America, the building of the Panama Canal, and the Johnstown flood are placed within the context of geological, meteorological, astronomical, and oceanographical processes. Applying critical thinking and experiential learning, young learners also explore how earth science processes often become hazards. Grades 6-12.