Storyline Narrative 7.2.4
Standard 7.2.4: Develop and use a scale model of the matter in the Earth’s interior to demonstrate how differences in density and chemical composition (silicon, oxygen, iron, and magnesium) cause the formation of the crust, mantle and core.
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Student Friendly Objective: I can create a scale model of the Earth based on density and chemical composition.
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Anchor Phenomenon: Seismic waves travel through the earth in an interesting pattern.
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Big Idea: The interior of the Earth has layers.
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The earth’s structure is composed of different layers. The teacher engages students with observations about how seismic waves behave in the earth and data of the earth’s interior (episodes 1 and 2). Students graph the data, look for patterns in the data, and ask questions about their observations.
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Students explore the structure of Earth’s interior by focusing on density. Using density stations, students make observations, ask questions, and carry out an investigation into what causes the phenomenon at each of the stations (episode 3).
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Students elaborate by doing research on the density of materials found in Earth’s interior (episode 4). They can also do an enrichment activity where they observe how pressure affects the density of a material (episode 4b).
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Students take their density data and create a scale model (episode 5). Students will communicate information when they use what they have learned to construct an argument using evidence as why Earth’s interior has four separate layers.
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Evaluation of student proficiency is determined by the assessment.
Episode 1
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Question
How do seismic waves travel in the earth?
Snapshot
Students observe a seismic wave animation as the teacher plots points on a whiteboard or paper.
Conceptual Understandings
Scientists can tell things about the earth’s interior by observing how seismic waves behave during earthquakes.
Why do the waves behave differently at different points in the earth? Why are there layers?
Conceptual Understandings
Materials with different densities will naturally separate.
How does density affect the structure of the Earth’s interior?
Snapshot
Students create graphs from data given to them from the teacher. Students look for patterns and ask questions. The teacher leads a class discussion directing students to recognize difference in layers.
Episode 2
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Question
How do scientists know that the Earth’s interior has distinct layers?
Episode 3
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Question
Why does matter separate?
Snapshot
Students observe density simulations as they question and find explanations as to why matter separates.
Conceptual Understandings
The Earth’s interior is made of different layers with distinct chemical compositions that naturally sort themselves into four layers.
How does density affect the structure of the Earth’s interior?
Episode 4
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Question
How does density affect the structure of the Earth’s interior?
Snapshot
Students research the density of materials found in Earth’s interior and determine which layer these would be found.
Conceptual Understandings
The Earth’s interior is made of different layers with distinct chemical compositions that naturally sort themselves into four layers.
What does the structure of Earth actually look like?
Episode 4:
Extension Activity
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Question
How does pressure affect the density of a material?
Snapshot
Students are shown a demonstration using bread where the materials don’t change but the density does.
Conceptual Understandings
Applying pressure to a material can increase the density, which explains the density differences between the inner and outer cores.
What does the structure of Earth actually look like?
Episode 5
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Question
What does the structure of the Earth actually look like?
Snapshot
Students create a scale model of the Earth, using information about each layer’s thickness, density, and composition.
Conceptual Understandings
The Earth’s interior is made of different layers with distinct chemical compositions that are sorted into four layers.