ALEX Lesson Plan

Students will develop a scale model of the sun, Earth, and moon system based on a one-meter sun. Students will first interact with a technology-based scaled model and view a video clip on scaling the solar system. Students will then scale the diameter of the Earth and moon, as well as the distance from the Earth to the sun, and from the Earth to moon. Students will be required to utilize mathematical skills, such as division, rounding, and metric system conversions. After scaling the diameters and distances, students will create the scaled model. 

This lesson results from a collaboration between the Alabama State Department of Education and ASTA.

Student Materials

Pencil (for each student)

Calculator (for each student)

Metric ruler (for each student)

Protractor (for each student- if available)

Blue paper (one sheet per student)

Gray paper (one sheet per student)

Teacher Materials

One-meter sun model (could use a large beach ball, or make model from yellow paper)

Area at least 108 meters in diameter

Student digital device-laptop/tablet (if available)

Teacher computer with internet capabilities

Interactive Board or projector

"Sizing Up the Universe"-Smithsonian Education Interactive Website

"A Scale Model of Our Solar System" Video Clip-7:06 Minutes

For Extension:

Enchanted Learning-The Planets: This website contains a data table with the diameter of each planet, as well as each planet's distance from the sun.

Students should understand that the Earth is orbiting around the sun while the moon is orbiting around Earth. In addition, students should understand that the solar system is so vast, that we have to scale it down in order to understand the relationships between objects in our solar system. Students should be able to develop a scale model with teacher assistance, and be able to round to the nearest whole number and complete metric system conversions (millimeters to meters and centimeters). 

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.)

The teacher will informally assess students as they complete the math problems required by the scale factor.

The teacher will informally assess students as they use their scaled models of the Earth and moon to create a model of the entire sun, Earth, and moon system.

The students will be formally assessed by completing the "Scaling the Sun, Earth, and Moon Reflection" handout. The teacher can count this assessment as a course grade, or use this reflection handout to facilitate a class discussion on the model.

Students who can easily create the scaled models of the sun, the Earth and the moon can use the same scale factor to create models of the other planets in our solar system. Students can also use the same scale factor to calculate each planet's distance from the sun, and add their models to the class model of the sun, Earth, and moon system.

The following website contains a data table with the diameter of each planet, as well as each planet's distance from the sun:

Enchanted Learning-The Planets

Note: Be sure to remind students to use the measurement in kilometers (not miles)!

Students who struggle with the mathematical portion of this lesson could be partnered with a student who excels in math, in order to provide support during that portion of the lesson. The teacher should also provide support to these students during that portion of the lesson to ensure the students are using the correct measurements for the model. If the mathematical skills required for this lesson would prevent the student from creating the scale model, the teacher could complete the math problems prior to the lesson, so that the student could focus on creating the actual model.