Soils
Lesson 6
How Quickly Do Soils Settle In Water?
Students continue to study the properties of the three soil components by conducting a settling test. In this test, they compare how the three soil components settle in a tube of water. Students then record results by drawing and labeling each settling sample.
3. Lesson set up and Management
SYSTEMS 1.1-Properties: Understand how properties are used to identify, describe, and categorize substances, materials, and objects and how characteristics are used to categorize living things
GLE 1.1.1 Understand simple properties of common natural and manufactured materials and objects: Sort common materials and objects using a simple property and Identify and describe the differences between common natural and manufactured materials and objects using properties.
GLE 1.1.5 Understand physical properties of Earth materials: Sort rocks based on size, shape, and other physical properties and Explain how some Earth materials are used by living things
SYSTEMS 1.2-Structures: Understand how components, structures, organizations, and interconnections describe systems
GLE 1.2.3 Know that common materials are made of smaller parts: Sort objects based on component parts
INQUIRY 2.1-Investigating Systems: Develop the knowledge and skills necessary to do scientific inquiry.
INQUIRY 2.2-Nature of Science: Understand the nature of scientific inquiry
- Soil contains particles of different sizes.
- Soil may contain animals, plants and their remains.
- Sand, clay and humus are three of the basic components in soil.
- Every soil component has unique properties that can be identified using simple tests.
3. Lesson set up and Management
Materials:
Although teachers may choose to run copies of Record Sheet 6-A “After I Shake the Tubes,” it is very simple to have students draw and label the tubes in their notebooks. Take a minute to teach students how to draw the tubes so they have reasonable diagrams: 1) draw a short horizontal line for the tube bottom, 2) draw two parallel vertical lines up from the horizontal line, 3) draw a cap on the top.
The teacher's guide book shows that a folded half-sheet of paper can help students get the soil into a tube. Students still spill a fair amount this way. An alternate idea is to show students how to make a cone-shaped funnel from their half-sheet of paper and insert the tip of the funnel partway into the mouth of the tube. They can pour soil into the tube through the paper funnel.
The funnel method of getting soil into the tubes. |
Another method of getting soil into the test tubes. |
The plastic 9 oz. cups to be used as tube holders will tip with just one or two tubes in them. Be sure students are aware of this and handle carefully, balancing several tubes around the sides of the cup.
Be sure students only fill each tube about ½ to 2/3 full of soil so they can shake the soil in the water and get soil movement.
Student Management:
It takes two to get the soil into a test tube! |
Students need to work together, with one holding the tube while the other pours the soil.
The same student should shake each time to control the variable of how the soil is shaken. To discourage student argument about who gets to shake, be sure to alternate this type of activity in each lesson.
Keep a thumb on the cap while shaking the tube! |
Have students put down half-sheets of newspaper the make clean up easier.
As students shake the tubes, have them hold their thumbs over the cap. The caps can come off during shaking, which makes a real mess on kids and in the room.
Writing Support:
Have students write a prediction as to what will happen if they shake the tubes again. Remember: a good prediction states the variable changed/manipulated (shaking) and the variable measured/responding (how the soils settle).