In this online activity, learners see simulations of how processes shape the Earth, and see estimates of how long these processes take. Learners see a before picture and after picture and need to choose a process (e.g. wind, water, volcanoes, glaciers) and a time span (e.g. 100 years, 10,000 years, 2,000,000 years) that could be responsible for the change. Use this as an introduction to Earth's changes or as a quick review. When learners set up a free account at Kinetic City, they can answer bonus questions at the end of the activity as a quick assessment. As a larger assessment, learners can complete the Smart Attack game after they've completed several activities.