Solar systems on a blue background.

Understanding Our Solar System

Grade 4 - Grade 6



About the author

Working alongside rural, remote, Indigeous, and other communities, Pinnguaq delivers programs to cultivate STEAM skills through innovative technology, art, and play.


In this lesson, students come to understand the solar system in which they live. They will learn what makes a planet habitable and why most planets are inhabitable. The guiding question for this lesson is: Is there another planet that can sustain life?

Learning Objectives

  • Students will know the eight planets—their names, order, and sizes
  • Students will be able to describe different characteristics of planets in the solar system
  • Students will be able to explain why Earth is the only habitable planet in our solar system


Suitable to live in
The gases surrounding the Earth or another planet

Introduction to the Solar System

To start the lesson off, the teacher will engage the students in a discussion around what the students already know about the solar system and the planets in the solar system. Activating prior knowledge, students will be asked what planet we live on. Students will be asked to name what they already know about space, such as our own planet, the moon, the sun, etc. 

Reading Activity

Read the story There’s No Place Like Space! by Tish Rabe.

“Au revoir, Pluto! In this newly revised, bestselling backlist title, beginning readers and budding astronomers are launched on a wild trip to visit the now eight planets in our solar system (per the International Astronomical Union’s 2006 decision to downgrade Pluto from a planet to a dwarf planet), along with the Cat in the Hat, Thing One, Thing Two, Dick, and Sally. It’s a reading adventure that’s out of this world!”

Engage in discussion after reading the story. Ask students to share anything that stood out to them and to name the planets. Ask if they know why Earth seems to be the only planet that can sustain life.

Modelling the Solar System


  • 30 cm  square of yellow construction paper to act as the sun
  • Nine images of the planets on index cards or drawn by the students
  • Ruler
  • Large space for students to demonstrate the solar system (classroom)

What to do:

Have one student hold the image of the sun in the centre of the classroom. Ask a few other students to hold the planets. One by one, ask the students to place themselves around the sun based on the measurements given by the teacher. 

Use the following measurements:

  • Mercury: 2.5 cm
  • Venus: 3 cm
  • Mars: 5 cm
  • Earth: 7 cm
  • Jupiter: 29 cm
  • Saturn: 48 cm
  • Uranus: 96 cm
  • Neptune: 152 cm

Ask students what they notice about the distance of the planets from the sun. Where would the hottest planet be? Where would the coldest planet be? Where is Earth in relation to these points?

A Habitable Planet

Ask the students what they think makes Earth habitable. They saw from the demonstration that Earth is not too far from the sun but not too close either. The sun is a very important element in our solar system. It is what the planets in our solar system rotate around. The sun provides heat and light which helps plants on Earth grow. But what else helps make Earth habitable? What about our atmosphere? 

Watching Activity

Research Project

In this research project, students explore whether we could live on another planet in our solar system. Ask the students: What if we lived on another planet? What would we need to survive on a really hot planet like Mercury? What would we need to be able to survive on a really cold planet like Neptune? In groups of two, choose a planet of your choice and research the elements of that planet. Is the planet hot or cold? Is it solid or gaseous? Thinking about the elements that make Earth habitable, come up with ways one can survive and make a different planet in our solar system habitable. Create a poster with your research findings and drawings of how you would survive on another planet.


Showcase group research projects around the classroom, asking students to circulate the room and comment on their peers’ projects.

Additional Resources

This article originally appeared in the fifth issue of Root & STEM, Pinnguaq’s free print and online STEAM resource supporting educators in teaching digital skills