This Formative works with the Glencoe Virtual Lab "How are materials from the earth broken down?" It is incldued as a link in the Weathering and Erosion Mastery Quest and is meant to have students identify some of the agents of weathering.
Open http://www.glencoe.com/sites/common_assets/science/virtual_labs/E06/E06.html in a new tab. Choose Scene 1