Total Duration: |
61 to 90 Minutes |
Materials and Resources: |
Student Materials: One per group Dipole bar magnet Gallon-sized plastic bag (for example, Ziploc) White paper Iron filings or magnetic metal chips (at least one teaspoon per group) Round piece of colored paper (cut to a diameter the same length of the bar magnets) Student Materials: One per person "Earth's Magnetic Shield Inquiry Activity" student sheet located in the attachments Notebook paper Pencil |
Technology Resources Needed: |
Teacher computer with internet capabilities Interactive Board or projector "When Nature Strikes-Science of Natural Hazards: Space Weather" video clip from the National Science Foundation-5:46 minutes For background information: "The Mystery of the Earth's Core Explained" video clip from DNews on youtube.com-3:27 minutes Informational articles for extension activity: "What causes the aurora borealis or northern lights?": from earthsky.org "Aurora Borealis: What Causes the Northern Lights & Where to See Them": from space.com "About Aurorae": from nasa.gov |
Background/Preparation: |
Earth's outer core consists of liquid metal, mainly iron and nickel. Due to the intense heat emanating from the solid metal inner core, convection currents are created in the molten metal of the outer core. Convection currents occur when the liquid metal of the outer core is heated, becomes less dense, and rises, as the molten metal rises away from the heat of the inner core, it cools, becomes denser, and sinks. These continuous convection cycles, along with the force created by Earth's rotation, generate electric currents which produce Earth's magnetic field. Although it is not necessary for students to possess this background information to complete this inquiry-based lesson, it would be beneficial to introduce these concepts to students before teaching this lesson. Alternatively, the teacher could extend this lesson by teaching these concepts after the inquiry. This video clip provides information about the magnetic field created by the outer core: "The Mystery of the Earth's Core Explained" from DNews on youtube.com Students should have a basic understanding of magnetism and know that magnetized objects can be attracted to or repelled from each other. Students should also know that the Earth is similar to a magnet, in that it has two poles: one that is positively charged and one that is negatively charged. If students do not have experience with the forces of magnetism, it would be helpful for the teacher to allow students to explore the attracting and repelling forces of dipole magnets. |
Before Strategy/Engage (20 minutes)
During Strategy/Explore & Explain (30 minutes)
Note: Be sure that the iron filings/magnetic metal chips do not come into direct contact with the bar magnet. They will stick to the magnet and be very difficult to disconnect. After Strategy/Explain & Extend (20 minutes)
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Assessment Strategies |
The teacher will informally assess students as they complete the inquiry to be sure the procedures are followed accurately. The students will be formally assessed by completing the "Earth's Magnetic Shield Reflection Questions" handout to explain how Earth's magnetic field provides protection from cosmic radiation. The teacher can count this assessment as a course grade or use this reflection handout to facilitate a class discussion on the model. |
Acceleration: |
Students who meet the Primary Learning Objective can conduct research on the aurora borealis (northern lights) and aurora australis (southern lights), which occur when solar particles interact with Earth's magnetic field and atmosphere. After conducting research, students can present their findings to their classmates. The following websites contain information about the northern and southern lights: "What causes the aurora borealis or northern lights?": from earthsky.org "Aurora Borealis: What Causes the Northern Lights & Where to See Them": from space.com "About Aurorae": from nasa.gov |
Intervention: |
Students who do not have prior experience with the forces of magnetism should be given time to explore how magnets interact with each other. The teacher can provide students with two dipole bar magnets and allow students to feel the magnetic forces of attraction and repulsion. The teacher should provide assistance to students as they perform the inquiry to ensure the procedures are being followed accurately. |
View the Special Education resources for
instructional guidance in providing modifications and adaptations
for students with significant cognitive disabilities who qualify for the Alabama Alternate Assessment.
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