Making Soil

Time - 30 minutes

Student Outcomes
Given items from material lists, student will be able to:

1. Rub two pieces of rock together over paper plate.
2. Drop water from eye dropper on pile of rock accumulated on paper plate and describe observed changes.
3. Give properties of rock on request.

Materials

• sandstone* - at least 2 pieces each
• shale* - at least 2 pieces each
• paper plates
• cups
• eye droppers
• water
• spoons
• newspapers
• paper towels

Vocabulary

• shale
• sandstone
• properties

Focus

"Yesterday we observed soil. What did we discover was in the soil?" (list resources on board) Review the idea of living and nonliving things found in soil.

Procedure

1. Have the getters pass out plates, newspaper, spoons, eye droppers, and paper towels.
2. "I am passing out rocks to each of you. You may take the rocks out of the bag, hold them, and look at them carefully. What are some properties of your rock?" (response)
3. "I have two rocks here; do you think any of the rock will break away if I rub them together?" (response) "Let's find out. I want each of you to rub the rocks together over your paper plate." (Model if necessary — monitor and make sure students are getting some rock dust. Pass out cups of water.)
4. "Now take your eye dropper and drop some water on your pile of rock dust. How did the pile of rock dust change?" (response) "Take your spoon and stir the mixture. What is your mixture like?" (response) "Can you make fingerprints on your plate with the mixture?" (have them try) "We call this rock, shale."
5. "Please put your rocks back in their bag. I am collecting them now and I am passing out some different rocks. You may take them out and look at them. What are some properties of these rocks?" (response) "What do you think will happen if we rub these rocks together?" (response) "Let's rub them together and find out. Rub them over a clean area of your plate. How are these rocks different from the shale?" (response)
6. "Now put a drop of water on this pile of rock dust. How is it different from the first one we did?" (response) "Stir your mixture. Would this make a good fingerprint?" (try and see) "We call this rock, sandstone."
7. Collect rocks; have getters return materials and clean up.

Closure

"One of the ways soil is made is when rocks break apart into very small pieces. Remember how hard it was to get the shale to break apart?" (yes)

"It takes many, many years to make just a little bit of soil on the earth. It is very important for us to take care of the soil we have."

"How did the material you had on your paper plate look like the soil we found outside when we played 'I Spy.'"

"What properties did the sandstone have? What properties did the shale have?"

Notes:

*Upon request, your local conservation district will provide pieces of sandstone and shale.

See Appendix for a Soil Recipe and Kansas State Harney Silt Loam fact sheet.