Last updated: August 16, 2022
Lesson Plan
Plate Tectonics
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- Grade Level:
- Upper Elementary: Third Grade through Fifth Grade
- Subject:
- Science
- Lesson Duration:
- 30 Minutes
- State Standards:
- Colorado Academic Standards for Science:
3.2.a - Identify how forces change Earth’s surface
3.2.b - Explain factors that change Earth’s surface - Thinking Skills:
- Understanding: Understand the main idea of material heard, viewed, or read. Interpret or summarize the ideas in own words. Applying: Apply an abstract idea in a concrete situation to solve a problem or relate it to a prior experience.
Essential Question
What causes events on Earth's surface such as earthquakes or mountain building?
Objective
Students will be able to explain how scientific theories develop, specifically the theory of plate tectonics.
Background
In science, theories are proposed explanations put forward by scientists that have been tested and have evidence to support them. Evidence is used to help support or disprove a theory. Geologists and paleontologists develop theories (e.g., plate tectonics) using evidence they find in the field (e.g., fossils).
The plate tectonics theory states that Earth’s crust is broken into plates that move. The interaction of plate movements results in earthquakes, volcanoes, mountain building and separation of continents. Geologists, just like other scientists, use a variety of evidence to support their ideas.
In 1915, Alfred Wegener was credited with the development of the modern theory of plate tectonics. His theory is based on geological, paleontological and climatological evidence. Some of the things he noticed were: 1) similar rock sequences of the same ages found on separated continents, 2) similar extinct plant and animal fossils are found on continents separated by large distances, 3) mountain ranges and glacial deposits match up when continents are pushed together as a continental puzzle, and 4) continental shapes. These observations suggest the continents were connected at one point. This large landmass of continents is called a supercontinent. Pangaea (or Pangea) was the most recent supercontinent.
Then in the 1950’s, scientists reignited an interest in paleomagnetic research, which generated massive support for the theory of plate tectonics. The magnetic direction recorded in an igneous rock at the time of solidification is called paleomagnetism. Small iron minerals in magma and lava align with the polar magnetism of Earth before the molten rock solidifies. These minerals therefore point toward the magnetic north. If the rock(s) moved after the magnetic direction was recorded, the rock compass will not align with Earth’s poles, which is how scientists are able to determine that the original position of the rock has moved over time. Recently formed rocks are aligned with the magnetic north of today. However, ancient rocks vary in orientation and in direction.
Preparation
You will need:
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Continent templates
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Fossil evidence
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Pangaea map
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Scissors
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Pencil
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Crayons/markers/colored pencils (optional)
Materials
Templates for continent cutouts
Lesson Hook/Preview
In science theories are explanations proposed by scientists that are then tested to see if they are correct. Evidence is used to either support or disprove a theory. Geologists and paleontologists develop theories using the evidence they find in the field such as fossils. A scientist named Alfred Wegener is credited with developing the modern theory of plate tectonics. In this activity you will explore this fun theory that Wegener gave us.
Procedure
#1: Try to name each continent. Write their names on them with the pencil. You can look at a world map to help.
The theory of plate tectonics states that the Earth's crust (the fourth layer of the Earth) is broken up into pieces or plates that move while floating on the denser mantle. It is the movement of these plates that cause things such as earthquakes, volcanoes, mountain building, and the movement of the continents.
#2: Cut out the continents by cutting along the dotted lines. Line them up how they would appear on a map of the world. If you would like to, color them in. Do you notice anything about their shapes?
#3: Try to arrange the continents so that they fit together like a puzzle.
Wegener's theory was based on geological, paleontological, and climatological evidence that he found. Some of the things he noticed were
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the shapes of the continents fitting together like puzzle pieces
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similar rock sequences of the same age found on separated continents
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fossils of the same paleontological plants and animals separated by distant continents
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mountain ranges and glacial deposits that match up when continents are pushed together
#4: Look at the fossil evidence that Wegener found and see if it helps you fit the continents together.
What Wegener found suggests that at some point in time the continents had all been connected. The large landmass created by all the continents being joined together is called a supercontinent. It is likely that over Earth's long lifetime multiple supercontinents have been formed and broken apart. The most recent supercontinent was named Pangea (meaning "all earth"). This is the Pangaea that the dinosaurs were walking on.
#5: Look at the provided map of supercontinent and compare it to your arrangement of continents. Were you close?
Vocabulary
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Theory: noun; an idea that is the starting point for argument or investigation
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Evidence: noun; material presented to prove or disprove something and help find the truth of a matter
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Continent: noun; one of the great divisions of land on the globe (Europe, Asia, Africa, North America, South America, and Antarctica)
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Plate Tectonics: noun; a theory in geology that states that the lithosphere or crust of the earth is divided into a small number of moving plates whose movement causes seismic activity such as earthquakes
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Paleontology: noun; a science dealing with the life of past geologic periods as known especially from fossil remains
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Paleomagnatism: noun; magnetic polarization in minerals in a rock which formed at the time the rock was formed
Assessment Materials
ReflectionThink about what you have learned during the activity and how it relates to today.
Did your puzzle change from the first attempt to second attempt in creating a supercontinent? Why or why not? Explain to the students that the supercontinent Pangea is just a theory and that they can defend their own supercontinent arrangement with evidence.
Do you think the tectonic plates are still moving today? Because they are! But scientists know that they move so slowly that we (usually) can't feel it.
What do you think could cause them to move? Most scientists agree that there are convection cells in the mantle where magma is rising and sinking in a circular pattern as it is heated by the core and cools under the crust. This causes the plates to be pushed along at the top of those circles. Sometimes the movement of the plates causes them to scrape against each other or get pushed under or over one another. This is what causes earthquakes. Have you felt an earthquake before? If so, you have firsthand experience with evidence of the plates moving!
Why do you think animals in Australia are so different from those on other continents? Scientists believe that Australia broke off from Pangaea earlier than the rest. That allowed the animals on the new continent to adapt to their surroundings separate from the other continents.
Additional Resources
Check out our Plate Tectonics Activity webpage for step by step instructions with pictures!