Earth, Moon and Sun Scale Models NGSS MS ESS1-3


In the Earth, Moon and Sun Scale Models mini unit, students calculate the diameter of a basketball to determine if it would qualify for the NBA! Then, they use this information to calculate the diameter of the sun, Earth’s moon and the other planets in our solar system.

Finally, students build a scale model to answer the question, “If Earth was the size of a basketball and the moon was the size of a tennis ball, how big would the sun and other plants be?”


Extension activities include comparing the mass and volume of Earth with other planets in our solar system.


Anchor Phenomenon Ideas: Share If the Moon Were Only 1 Pixel with students and let the discussion begin! Use the authentic questions they come up with to make connections throughout your unit.

Make it Relevant: We chose a basketball to represent Earth but you could swap a soccer ball, volleyball or kickball to make calculating diameter more relevant for your students.

Tips and Tricks: Connect with your math teacher for ideas about reviewing circumference and diameter. They are usually excited to help make interdisciplinary connections!

Make this experience as hands on as possible. Offer multiple types of balls to measure circumference. Focus on the big ideas and don't get bogged down with the numbers or math.

We've included an answer key to make things as simple as possible for you!

Ideas for Modifications: NGSS MS ESS1-3 asks students to "analyze and interpret data to determine scale properties of objects in the solar system". We take things a step further to meet the Minnesota standard 6E.3.1.1.1 that asks students to "develop and use scale models".

To modify this mini unit for SPED students and any kids who struggle with math, have them work through just one or two examples of the calculations with you. Then, provide them with the data to complete their table.

You want kids to understand what the data means. They do not need to memorize the math. Final models can be made simply with copies of basketballs.

Example of summative assessment

Enrichment Ideas: For an extra challenge, encourage students to learn more about the asteroid that created the Chicxulub crater. How large was the asteroid? Would this be considered a large, medium or small asteroid compared to those currently in the asteroid belt? How big is the impact crater and what were the consequences of the impact? Do we face any asteroid threats on Earth today?