Students contemplate the big idea that erosion affects the surface of the earth's crust. The teacher creates student interest with an anchoring event called RAP- Review and Preview. Focus and relevance for the lesson is emphasized by asking students to predict what will occur when water and classroom fan are applied to a pile of soil. Students investigate their school grounds and neighborhood for evidence that wind and /or water have created noticeable landscape changes. Students work in groups of 4-6 to make a scale drawing of the school area. They discuss ways that the erosion they observed could be rehabilitated, using an "I Wonder" format for developing ideas.