Total Duration: |
61 to 90 Minutes |
Materials and Resources: |
Student Materials (per group) Safety goggles Clear plastic container (for example, Sterilite or Tupperware container) Liquid food coloring White sheet of paper Plastic spoon Two Styrofoam cups Small pieces of paper (for example, chads from hole puncher) or glitter Timer Student Materials (per student) Student handouts provided in attachments Pencil Notebook paper Teacher Materials Water source: This lesson requires cold tap water, room temperature water, and hot water. The hot water can be heated with an electric kettle or hot pot. |
Technology Resources Needed: |
Teacher computer with internet access Interactive whiteboard and/or projector "100 Greatest Discoveries: Continental Drift" video clip from the Science Channel (2:12 Minutes) For background information: "100 Greatest Discoveries: The Core of Earth" video clip from the Science Channel (2:39 Minutes) |
Background/Preparation: |
Before beginning this lesson, students should be familiar with the layers of Earth's interior. Although we are unable to study the Earth's interior directly, scientists have studied the interior indirectly using seismic waves. The inner core is a solid sphere of dense metals, while the outer core is liquid metal. The cores are composed of mostly iron and nickel. The convection currents within the outer core create Earth's magnetic field. The layer surrounding the outer core is called the mantle, which consists of extremely hot rock. The upper part of the mantle is called the asthenosphere, this part of the mantle flows very slowly in convection currents. Above the asthenosphere, is the lithosphere, the brittle, rigid part of Earth's crust. The lithosphere is separated into tectonic plates which float slowly on the asthenosphere. Students should also be familiar with the concept of convection currents. Convection currents occur when a heat source is applied to a fluid substance. In Earth's interior, energy from the outer core heats the rock of the mantle, causing it to become less dense. This hot rock rises towards the lithosphere, where it cools, becomes denser, and sinks back towards the outer core. Although the convection currents in the mantle are very slow, they cause plate movements over millions of years. This video clip describes how scientists used indirect methods to discover the interior composition of Earth and describes where Earth's internal energy originates. "100 Greatest Discoveries: The Core of Earth" from the Science Channel-2:39 Minutes The assessment portion of this lesson will include questions relating to the control and experimental groups of the lab activity. Students will need to be familiar with the terms control and variables. Control: This is the trial the scientist performs before testing any variables. Variables: The factor the scientist changes between tests. |
Before Strategy/Explain: 15 minutes
During Strategy/Explore & Explain: 40 minutes
Lab Activity Summary: Students will begin the lab by setting up the control group. This will entail filling the plastic container with cold tap water and filling the two Styrofoam cups with room temperature water. Students will predict what will happen when five drops of food coloring are added to the water in the plastic container. Students will then add five drops of food coloring to the water and observe the movement of the food coloring for five minutes. Students will record their observations in a pictorial and written format. Students will repeat these procedures two more times: first, filling one of the Styrofoam cups with hot water, then by filling both of the cups with hot water. During the last test, students will add the small pieces of paper or glitter to the surface of the water. Students will observe and record the motion of these objects. Note: The lab activity handout instructs students to use the plastic spoon to stir the water between each trial to disperse the food coloring. If the water becomes too saturated to see the movement of the food coloring, students should empty the plastic container and fill it with fresh water. Safety Considerations: This lab activity requires students to handle hot water. Styrofoam cups are recommended for this activity to insulate the hot water. The teacher should provide safety instructions pertaining to hot water before beginning this inquiry. After Strategy-Explain & Extend: 20 minutes
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Assessment Strategies |
The teacher will informally assess students as they complete the lab activity to be sure the procedures are followed accurately. The students will be formally assessed by completing the "Convection Currents in the Mantle Reflection Questions" handout to determine if they can explain how this flow of energy could result in tectonic plate movement. 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 complete the Primary Learning Objective can be challenged to design another experimental group for the lab activity. The students could add additional heat sources, change the placement of the heat sources, or change the temperatures of the water. |
Intervention: |
The teacher should provide assistance to students as they perform the inquiry to ensure the procedures are being followed accurately. The teacher should closely monitor the students during the reflection portion of this lesson and provide support as needed. |
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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