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Introducing States of Matter Mark as Favorite (9 Favorites)

LESSON PLAN in Physical Properties, Phase Changes, Introduction, Molecular Motion, Matter. Last updated April 07, 2023.


In this lesson, students will investigate particle behavior in different forms of matter: solid, liquid and gas. Students will examine a model of the particles in the different states of matter and will also participate in a kinesthetic demonstration of matter. They will also learn what makes the states of matter different from one another when changing from one form to another.

Grade Level

Elementary school


By the end of this lesson, students should be able to

  • Identify three main states of matter as solid, liquid and gas.
  • Explain the differences in particle behavior in each state of matter.
  • Understand how particle interaction changes from one state to another.

Chemistry Topics

  • States of Matter
  • Phase Change
  • Physical Properties
  • Solid
  • Liquid
  • Gas


Teacher Preparation: 10 minutes

Lesson: 55 minutes


  • Anchor Chart on states of matter
  • 3 plastic plates
  • 50 marbles
  • Colorful copy paper (1 per student)
  • Crayons/pens/colored pencils
  • Scissors
  • Rulers
  • stickers
  • Why does Matter Matter?” article


  • No specific safety precautions need to be observed for this activity.

Teacher Notes

  • Create models for the particles of a solid, liquid and gas, by using three plastic plates and about 50 marbles (pomp oms or bouncy balls could be used instead of the marbles). Label the bottom of the plates: first plate “SOLID” and fill the plate with marbles until there is no room left between them to move. Label the second plate “LIQUID” and fill the plate with fewer marbles than the solid, leaving room for the marbles to roll around a bit. Label the third plate “GAS” and add around 5 marbles, giving them room to move freely.
  • Print “Why does Matter Matter?” article and questions for students to use.
  • Introduction:
  • Review what the states of matters are and ask for examples from the students.
  • Organize responses in an anchor chart (make three different columns)
  • Ask students what they think makes the states of matter different from one another and the same. Record their responses.
  • Let them know that it is hard to imagine that matter is made of particles since they cannot see the particles.
  • Explain that spheres are often used to represent the particles in each of the phases of matter.
  • Demonstration & Discussion
  • Use the 3 marble plates to show students a representation of the particle arrangements for the threee states of matter.
  • Ask them which one they think represents a solid, a liquid and a gas.
  • This is used to demonstrate the idea of how tightly packed the particles are in each state of matter as well as how they interact with one another.
  • After they have made their guess, have a discussion about the differences between each model.
  • Add a drawing of each of these to the anchor chart you made at the beginning of the lesson
  • Act it out
  • Students should stand up. They will use their body to represent a particle and together they will model how particles behave in the different phases of matter.
  • Use a designated amount of space for this activity (you can even outline an area with string or a ribbon.
  • To begin tell students they will be a solid. You can have students work together to determine what actions they should incorporate:
    • Students should move close together in the space.
    • Students should be bumping into each other a lot and shouldn’t be able to travel very far from their starting place.
  • Inform students that heat is being added, ask them what will happen. They should respond that they are going to move fast and melt.
    • Since the matter is changing into a liquid, the particles are vibrating with more energy and should spread out within the space.
  • Finally the liquid is going to change phases again, ask the students what will happen. They should say they are evaporating and boiling, and will vaporize.
    • They should spread really far out and move around vigorously.
  • Read about it
  • Pass out the “Why does Matter Matter?” worksheet. Read through the article and have a discussion after completion.
  • Revisit your anchor chart and add anything new students have learned about the molecules in the states of matters.
  • Foldable
  • Pass out a piece of copy paper and scissors to each student.
  • The paper should be folded in half landscape wise.
  • Then, have students measure about 3 ½” from both ends drawing a vertical line to create where the three cuts will be for the flaps.
  • Students should cut at the marks.
  • Label the front like shown in the first picture below.
  • Open up the flaps and draw a picture of each state of matter and on the bottom flap label like in the second picture.
  • Don’t show students where to place the particles (stickers) - have them fill in the correct information and place stickers themselves based on what they have learned.
  • Check foldable for student understanding.

Cross-Disciplinary Extensions

Connect to Writing
Students can write a poem, comic strip or story to describe how molecules interact with each other in the states of matter.