For nearly five billion years, the Earth's surface has been constantly built up and broken down by processes taking place above and below the Earth's surface, resulting in the wide range of beautiful and complex landscapes we see today. In this unit, students will continue to make connections between the Earth's systems when they study interactions between the lithosphere, atmosphere, hydrosphere, and biosphere by investigating the rock cycle, and the erosional processes of streams, wind, wave action, and mass movement.