"Layers Upon Layers"

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Social Studies

OBJECTIVE

Students will construct a model of rock layers and infer the relative ages of the layers within the model. They will complete an activity sheet to express what they have learned.
 

MATERIALS

flour
sand
salt
yellow cornmeal
small scoop
plastic cups
pencil/paper
 
 

PROCEDURES

1)  Raise your hand if you have ever seen different layers on a rock?  Why do you think there are different layers?
2)  Look at this picture of the Grand Canyon. Do you see all of the different layers of rocks?
3)  Today we are going to see how rocks have different layers and how these layers have different ages by making our own models.
4)  In teams, students are to:
        a. Scoop a layer of sand into the bottom of the cup.
        b. Next, scoop a layer of salt on top of the sand.  Do not mix the layers.
        c. Add a layer of cornmeal.
        d. Add a layer of flour.
5.  Teacher will do the same.
6.   Which layer did you put in the cup first? last? -Pretend you found a bone in the layer of salt.  How many layers would be above the bone? (two)
7.  Suppose these layers were rock.  Which one do you think would be the oldest? (sand)  Which one would be the youngest? (flour)
8.  Students will complete an activity sheet reviewing the concepts of age.
 

EVALUATION

Assessment from oral answers and activity sheet.