Before Strategy/Engage-15 minutes
1. If students have access to a digital device (laptop/tablet), they should visit the website Smithsonian Education "Sizing Up the Universe" Interactive . If students do not have access to a digital device, the teacher can display the interactive on the digital whiteboard.
2. Instruct students to travel through steps 1-5 of this interactive. This will give students a beginning understanding the scaled sizes of the Earth, the moon, and the sun, as well as the diameter of each objects' orbit.
3. Students will view "A Scale Model of Our Solar System". After students view the video, the teacher should ask the students, "Why did the men in the movie have to go all the way to a desert to create their scaled model of the solar system?"
Possible answer: The solar system is so big, they had to find a fairly large area to recreate their scaled model.
4. Explain to students they will be creating their own model of the solar system, for now, just focusing on the sun, Earth, and the moon.
During Strategy/Explore & Explain-60 minutes
1. Students will need the "Scaling the Sun-Earth-Moon System" handout.
2. The teacher will lead students through the first scale conversion (sun's diameter). (See "Scaling the Sun-Earth-Moon System" Handout for detailed directions for steps #2-4).
3. The teacher will demonstrate the second scale conversion (Earth's diameter). Students will complete the problem on their handout.
4. Students will complete the third scale conversion independently or with a partner. The teacher will informally assess students as they are working to ensure they are understanding the scale conversion.
5. The teacher will lead students in the scale conversion for the distance from the Earth to the sun. (See back of "Scaling the Sun-Earth-Moon System" handout for steps #5 and #6.)
6. Students will complete scale conversion for the distance from the Earth to the moon independently or with a partner. The teacher will informally assess students as they are working to ensure they are understanding the scale conversion.
7. The students will use a ruler and/or protractor to measure a circle that is 2 millimeters in diameter on the gray paper (if no gray paper is available, students may use white paper and color it gray). Students should label this object "moon".
8. The students will use a ruler and/or protractor to measure a circle that is 9 millimeters in diameter on the blue paper (if no blue paper is available, students may use white paper and color it blue). Students should label this object "Earth".
Note: Students could partner for steps #7 and #8, with one student representing the moon and one student representing the Earth.
9. The teacher will take the class to an area that is at least 108 meters in diameter. The teacher will represent the sun by standing in the middle of the area with the sun model (beach ball one meter in diameter or paper model).
10. Students will begin at the sun (teacher), and walk 108 meters outward. Students can measure exactly with a meter stick, or they can estimate the measurement with 108 large steps or 216 small steps. Students will place their "Earth" model on the ground.
11. Students will use a ruler to measure 28 centimeters away from their "Earth" and place their "moon" in that location.
Note: If students are working in partners, one partner can hold the "Earth", while the other student measures and holds the "moon" 28 centimeters away.
12. Ask students to look towards the sun and at their "Earth" and "moon" models. If students have the capability to take a picture with a digital device, they could take a picture of the sun mode from their vantage point of "Earth".
After Strategy/Explain & Extend-20 minutes
1. Students will complete reflection questions on the model. This will include a sketch of the model, as well as questions to check for student understanding of the concept. (See "Scaling the Sun-Earth-Moon System Reflection" handout.)