| background & resources
Each group needs the following supplies:
1 Tube (18" clear plastic water-tight tube with PVC caps on both
ends, OR a clear plastic tennis ball can
4 film canisters: diatomaceous earth, sand, soil, pebbles
Hand lenses--1 for each student
Water to fill tube
Large Ziploc bag or large grocery bag
1. Pour about a teaspoon of each of the materials in the film canisters in separate piles a piece of paper. Examine the four materials with a hand lens. Discuss with your group how they are alike and how they are different.
2. If the wind was to blow across these four materials, which would move in the lightest winds? Which would need a greater force?
3. Lay the Ziploc bag on the table. One partner holds it open, forming a "cave." Place about 1/4 of the materials from each film canister in a separate pile inside the lip of the bag.
4. Use the straw to blow across the piles to see which moves in the wind the easiest. Which takes more force? Share your group's ideas with the whole group. Is there agreement, or do some groups have differing ideas?
5. Rivers and streams carry large amounts of sediment as they move. What happens when rushing waters of a river meet larger bodies of water and slow down? Discuss this with your group and share your ideas with the larger group.
6. If all four materials are mixed in water, what will happen? Share your ideas in your small group.
7. Draw a model of your group's prediction on the student worksheet.
9. Pour all materials from the canisters, the Ziploc bag, and the paper on which you first observed the materials into the large tube.
10. Fill tube with water.
11. Place caps securely on the ends.
12. Shake the tube to mix all materials.
13. Set it on a flat surface and let it stand without any more disturbance.
12. Make observations over the next ten minutes. Discuss how the materials are acting in the water. How is it changing? Compare your prediction to how the tube looks at the end of the period. Draw your observation. Make notes and labels to explain what you observe.
13. Take five minutes during each of the next three days to make a new observation. Record how the sediments in the tube have changed.
Discussions Questions/Extensions ......
Write a paragraph explaining what you have observed in the sediment tube activity. Relate your observations to how sediments in streams and rivers act. Describe how this model is like real rivers and streams. How is it different?
Return to top of page
Back to: TEA Activities Page
| background & resources