1. The class will review the concepts of watersheds, drainage divides and drainage basins. Ask students to think about what creates the drainage divides in watersheds. Students will discuss their ideas.
   
2. The class will be divided into small groups. Each group will receive a tray, marker, newspaper, aluminum foil or plastic wrap and tape. Students will crumple newspaper into small balls and randomly tape them down in the tray. The students will place aluminum foil or plastic wrap over the newspaper so it follows the contours of the crumpled up newspaper to simulate the topography of mountains and valleys. A book will be placed under one end of the tray so that it is elevated to simulate the sloping of land toward the sea.
   
3. Using the marker, the students will draw on the aluminum foil where they predict the drainage divides will occur in their models and where water might collect in pools. Bring the spray bottle(s) filled with blue colored water to each group, and have students spray several pumps of water on the model (for management purposes, you may want to do the spraying yourself). Students will observe how the water flows, what direction it moves and where it collects and compare this with their original predictions. 
   
4. Students will examine the physical map of South Carolina and observe that some drainage divides occur where there do not seem to be any major elevation differences, such as in the Coastal Plain. In their trays, students will tape drinking straws or pencils down to the bottom and cover them with a sheet of aluminum foil or plastic wrap. Students will again predict where they think the water will flow. Again assist students  in spraying water and have students observe where the water flows. Students will infer from this that even slight elevation changes can form drainage divides.
   
5. Students will create a model of the state of South Carolina in their trays. Using newspaper, drinking straws and aluminum foil again, students will create a topography that simulates each region of South Carolina. The tray will have a definitely recognizable Mountain region, a Piedmont region, a Coastal Plain region and an Ocean. The model will also represent the four major watersheds of South Carolina (Savannah, PeeDee, Santee and Coastal Rivers) and drainage divides will occur in similar positions to those found in South Carolina. When water is poured on their model, the water will flow from the mountains to the sea and major drainage basins will be the same. Students do not need to worry about reproducing the position of rivers, streams, mountains and reservoirs, just watersheds and ecoregions. The model does not need to be the shape of South Carolina, but can fit the shape of the tray.

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Follow-up questions

1. How accurate are these models? When it rains on soil, does all of the water stay on top of the soil and run off like it does on aluminum foil? Would some of the water become groundwater in the natural world? Does any of the water in the model become groundwater?
   
2. How do the Appalachian and Rocky Mountains affect the shapes of watersheds and the direction of water flow in the United States?
   
3. Is there anywhere in the United States where a watershed does not flow into one of the oceans or the Gulf of Mexico? Where and why?