A Rock Is an Earth Material Composed of Different Ingredients Called Minerals

Andrea Autenrieth

Science Lesson

Mock Rocks

5-5-2010

Learning Targets:

·  A rock is an earth material composed of different ingredients called minerals.

-I can state what rocks are made of.

·  A mineral is a rock ingredient that cannot be physically reduced to more elementary minerals.

-I can tell the difference between a rock and a mineral.

Curriculum Used: FOSS Mock Rocks, Part two: Taking rocks apart

Lesson Plan:

Pre-Assessment

·  Before the lesson is taught, students are given a sheet asking these questions to test their background knowledge:

1. How can we know what the ingredients of a rock are?

2. How can we separate the ingredients of a rock?

·  Briefly touch on the lesson that occurred the day before, reminding the kids that they did a great job observing their mock rocks.

·  After their observations the day before, ask the students if they think that rocks are made out of one or many ingredients.

·  Tell students, “Today your challenge is to separate and identify as many of the ingredients as you can.” Explain an important job of a geologist is to find out what materials make up the rocks in the field. This information provides evidence about what the earth is made of.

·  Introduce their “geologist pick,” which is a nail. Explain that geologists use picks (maybe bring a real example in or draw a picture of one on the board) to take apart rocks to observe what they are made of.

·  Discuss using the nails safely.

·  Describe taking rocks apart:

a. Pairs can break the rocks in half and each student works with half on a paper plate.

b. Students use their “picks” to break the rocks apart and separate the different ingredients, sorting them into piles.

c. After sorting, students write their observations on the lines provided on pg 4 in the Earth Materials Notebook.

·  Take the rocks apart:

Distribute to each group of two: two paper plates, one mock rock, one nail, one hand lens, and a plastic cup. Students may begin when they receive all materials.

·  Define “Rock”

When students are done taking the rocks apart, sorting the ingredients, and recording their observations, discuss the difference between a rock and a mineral. Begin by defining rock.

A rock is an earth material made up of more than one ingredient.

Questions you could ask for discussion:

Can you identify the ingredients that make up your mock rock?

If you had a rock made of other ingredients, would it be the same as your mock rock? (No, different mixtures of ingredients make different kinds of rocks.)

Imagine you put all the ingredients back together. How would this new rock be the same and different?(Same kind of rock, different shape.)

·  Define “Minerals”

Help students define the difference between rocks and minerals. Have them look closely at the red gravel. Tell them,

If we took hammers and broke down the red gravel into smaller pieces, it would still be red gravel. So this red gravel is not a rock; it is made up of only one ingredient. When an ingredient cannot be broken down into other ingredients, it is called a mineral.

·  Have students record the list of mock rock “minerals” they have discovered so far on the bottom of pg 4 of their notebooks

·  Collect the gravel and shells

Have students put all the gravel and shells in the cup and have students bring the cups to the materials station. Keep the grey material on the paper plates.

·  Discuss separating the grey material

Ask students to look closely at the leftover material. Ask

Do you think the gray material can be separated further? How could you do that?

After a few minutes, ask the groups what they thought. Ask what would happen if we mixed the gray material with water. Discuss the possibilities.

·  Plan to add water

Show students the vials. Plan a procedure for mixing materials with water and observing the results.

a. have the students fill the vials 1/3 full with leftover gray material.

b. add water to the vials until it is about 1 cm from the top.

c. snap on the cap and hold it tightly while shaking for a few minutes.

d. observe the contents and draw a picture in the first vial outline on pg 5.

e. record observations on pg 5 of the notebook.

Distribute two vials, a cup of water and syringe (if you have one) to each group.

·  Discuss observations

Have students share their observations after shaking the vials. Here are some questions to use for discussion:

How has adding water helped to separate the rock ingredients?

What do you notice about the way the materials are beginning to settle?

What do you think will happen if the vials settle overnight?

Do you think that there is anything dissolved in the water? How will you know?

What will you observe if and ingredient dissolves? What will you observe if and ingredient doesn’t dissolve?

·  Let the vials settle overnight

Have the students label their vials with sticky notes and let the vials settle overnight in a safe place.

Post- Assessment

The students will return to the sheet and answer this question:

3. A student wrote in her journal, “A rock is like a chocolate chip cookie.” What do you think she meant when she wrote that sentence?

If there is time, ask the students to answer these questions:

“What is the difference between rocks and minerals?”

“How can the minerals in a rock be separated?”