In this lesson, students explore the causes of earthquakes and their impact on the geology of an area and on human societies. They begin by looking at the role tectonic plates play in creating the forces that cause earthquakes, to help them understand why earthquakes occur when and where they do. Hands-on activities illustrate how rocks can withstand a certain amount of stress, but that every material has its breaking point. When rocks break underground, an earthquake occurs. In the last section, students explore the impact earthquakes have on humans and look at the efforts scientists are making to better understand and predict these sometimes deadly events.