Beacon Lesson Plan Library

What Is the Matter?

Cheryle Borsos
Santa Rosa District Schools


What is the Matter? It's a solid, a liquid, or a gas. In this lesson, students explore and identify the phases of matter and compare the particle motion in solids, liquids, and gasses.


The student understands that matter may exist as solids, liquids, and gases.

The student knows that molecular motion increases from solids to liquids to gases.


- One latex balloon filled with carbon dioxide
- One latex balloon filled with helium
- Four or five sugar cubes
- Four or five marbles
- Four or five nails
- Four paper plates
- One wooden block
- One rock
- One jar filled with vegetable oil
- One jar filled with baby oil
- One jar filled with colored water (food coloring)
- A class set of Student Lab Investigation Sheets (Associated File)
- A class set of Concept Maps (Associated File)


1. Set up the demonstration jars and label them vegetable oil, rock, and oxygen.
2. Set up 8 lab stations around the classroom. Each station should have one sample of matter.
Station 1 = A jar of baby oil with a note card indicating that the sample is the matter in the jar.
Station 2 = A pile of sugar cubes on a paper plate.
Station 3 = A pile of marbles on a paper plate.
Station 4 = A balloon blown up with carbon dioxide taped to the counter top. Include a card indicating that the sample is the carbon dioxide in the balloon.
Station 5 = A jar of colored water with a note card indicating that the sample is the matter in the jar.
Station 6 = A pile of nails on a paper plate.
Station 7 = A helium balloon taped to the counter. Include a note card indicating that the sample is the helium in the balloon.
Station 8 = A wooden block on a paper plate.
3. Photocopy a class set of Concept Maps (See Associated File)
4. Photocopy a class set of “What Is the Matter?” Lab Investigation Sheets (See Associated File)


1. Activate student interest by asking them, which would be easier to hold in their hands, a baseball or 100 mL of dishwashing soap. Generate a discussion about why it is easier to hold the baseball. (The baseball has a solid shape. The dishwashing liquid has no shape and runs out of your hands.)

2. Inform students that they are going to be investigating three phases of matter. Ask students to describe matter. Allow them to share their ideas, but be sure to address any misconceptions that may exist. Define matter as anything that has mass and takes up space. Informally point out that matter is all the “stuff” that makes up the universe. All matter is made up of particles called atoms.

3. Explain that matter can exist in three states: a solid, a liquid, and a gas. ( Note: It is not necessary to address the fourth phase of matter, plasma, at this developmental level.)

4. Show students a jar of vegetable oil, a clear jar labeled oxygen, and a jar with a rock in it. Identify the oil as a liquid, the oxygen as a gas, and the rock as a solid. Ask the students to identify properties of each object. List the student ideas on the board under the categories: Solid, Liquid, and Gas. Ask them if any of the properties for one phase would apply to an object in another phase.

5. Next, ask them to think about what would happen to the shape of each substance in the jar if the jars were broken. (The oxygen would escape into the air, the oil would spill across the desk, and the rock would keep its shape.)

6. Guide students to understand that shape is one defining characteristic of matter. Solids have a definite shape. Liquids have no shape of their own; the particles take the shape of their container. Gas particles have no shape of their own; the particles spread apart filling all the space available to them.

7. Point out that solids and liquids have a definite volume; the amount of space they take up can be measured. However, gas particles move out to fill the space so it has no definite volume.

8. The next thing you want to teach the students is that the particles in all matter are in motion. Explain that the particles in a solid are packed very closely together. Because the particles are so tight, they move very slightly back and forth. The particles in a liquid are fairly close together, but unlike a solid, the particles in a liquid move around each other freely. This allows liquids to flow from place to place. The particles in a gas move at high speeds in all directions. The particles in a gas are the fastest moving of all three phases.

9. At this point, you should check for student understanding by having students complete a concept map of the three phases of matter. This can be used as a formative assessment. (See Associated File.) Explain that the students must fill in the missing spaces on the map using the word bank below the map.

10. After students have had a chance to complete the map, discuss the correct answers with the class. Clear up any misunderstandings before continuing.

11. Once students have been successful at identifying the characteristics of the phases of matter, inform them that they are going to do an investigation called “What is the matter?" (See Associated File.)

12. Pass out a “What is the matter?” Lab Investigation Sheet to each student. Read the procedures aloud with the class before inviting them to move to their lab stations. (See Associated File.)

13. If there are no questions, students will move to their assigned lab station and work with their partners to begin the investigation. Allow students 3 - 5 minutes at each station and then facilitate a rotation to the next station. It is helpful to rotate students in a clockwise rotation to ensure that all students get to all stations.

14. Once students have rotated to all eight stations, allow time for them to draw a conclusion and to complete the critical-thinking questions.


The concept map will be used as a formative assessment during the lesson.

The lab investigation sheet will be used as a summative assessment.


This lesson could be extended to include amorphous solids, such as plastics, rubber, silly putty, and glass. Amorphous solids are not crystalline solids because the particles are not arranged in a regular pattern.
In addition, this lesson could extend into a lesson on viscosity. Viscosity is the resistance of a liquid to flow. Students could engage in viscosity investigations for various liquids.
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