1. Lesson 66
Photocopy:

2. Mr. Petersen Bonneville Junior High
Lesson 66 9th Grade
Mr. Petersen
Bonneville Junior High

3. Self Starter Sheet 40 Points Possible Today’s Learning Objective and Questions
Learning Objective: Students will use the internet to research a natural disaster.
Essential Question: Describe the geosphere of the earth?
Answer: the land, topography, etc.

4. 9th Grade *Glossary List [ 1]
Ocean Ridge-
Rock Slide-
Hurricane-
Elastic Rebound Hypothesis-
Geosphere-

5. Constructive Response Question [ 3]
Explain how temperature and density drive convection currents and draw a model of molecules showing cold, warm and hot.
What role does gravity play in plate movement?
(As soon as we have about 4 questions students will be given a test on this material).

6. Answers
Temperature and density are related to one another. As a substance heats, it becomes less dense allowing it to rise if it is in a more dense substance. As it cools the density increases and it may sink.
Gravity allows for density differences to move plates. Molten magma can rise, cold solid basalt will sink. The plates move as a unit and are pushed and pulled by gravity resulting in movement.

7. Answer 1
Hot
Warm
Cold

8. Constructive Response Questions
Describe and evaluate the evidence for plate tectonics that you find the most important.

9. Answer Answers will vary
Discussion: The current theory of plate tectonics is supported by sea floor ridges where magma rising from inside Earth seems to push plates apart or be responding to the pulling apart of plates at other plate boundaries. Matching magnetic striping of rocks formed at ridges indicates new land formed at regular intervals along ridges. Dates of sea floor samples shows oldest rocks furthest from ridges.

10. Constructive Response Question [ 3]
Scientific history has many examples of important work being ignored by mainstream scientists. Why is it important that scientists be skeptical?
It is important to be skeptical because a single experiment or data set may not be representative of the whole. Scientists must demand a body of evidence before they can call a hypothesis a theory.

11. Correct Natural Disaster Reports