40 The History of the Earth: Supplemental Guide 2A | The Earth Inside-Out, Part I
Show Image 2A-8: Arches National Park- This stone in Arches National Park has been eroded over
time by wind, rain, and ice. Turn and tell your partner if you
think this stone was larger or smaller before it was eroded by
wind, rain, and ice. [Take a class tally. If necessary, clarify that
erosion makes things smaller.]
Crust
Show image 2A-4: Diagram of the layers of the earth - Today you will learn about the crust of the earth. [Point to the
crust in the diagram.] - Say crust with me three times.
- The crust is the hard, thick, outer covering of the earth. It is
represented, or shown, in this image as a thin, brown line.
[Invite a student to point to the crust.] - Gerry the Geologist digs a hole in the earth’s crust.
Ramon wondered if the earth’s crust was similar to or different
from pizza crust. - Many things can be found on the earth’s crust. Tell your
partner about some things you can fi nd on Earth’s crust. [Call
on several partner pairs to share.]
Purpose for Listening
Tell students that they have been talking about the surface of
the earth. Ask students if they remember what the surface of
something is. Explain that today they are going to learn about the
inside of the earth. Quickly review the concepts of in and on with
students. Tell them to listen carefully to fi nd out what the inside of
the earth is like.