Compositional Layering of Earth, focusing in this video on Continental vs. Oceanic Crust.
Then a look at a Structural Layering of the upper Earth into a Lithosphere vs. an Asthenosphere (rigid vs. plastic solids).
(Since this isn't Discovery TV, or Public Television, or Middle School, or Talk Radio, then don't EVER confuse the term "crust" with the term "lithosphere," etc., even when 60% of your classmates will...)