What's the Matter?:  The Three Phases of Matter

Lee McLaurin Edward Franklin Frazier School
4027 W. Grenshaw
Chicago Illinois 60624


This lesson can be modified to be taught to any grade level K-8, but it is
primarily for 4-6 grade. The students will be able to categorize materials as
solids, liquids, or gases. The students will be able to recognize examples of
the structure of the particles in solids, liquids, and gases.

Materials Needed:

1 Wood Block or Ice Block 1 Small Bowl 1 Pot
1 Glass of Marbles or Water 1 Box of Cornstarch
1 Balloon 1 Stirring Utensil
1 Hot Plate Food Color
1 250ml Beaker Water


The teacher introduces the topic by asking the students to name different
kinds of objects. Ask the students what all the items have in common. Point
out that all of the objects are composed of matter. Define matter as anything
that has mass and takes up space. Remind students that mass is the amount of
matter an object contains. Point out to students that matter has three
different phases (solid, liquid, and gas). Illustrate the particle arrangement
in the three states of matter. Show the students a glass of water or marbles.
If using the marbles, tell the students that the marbles represent the particles
of matter sliding past each other. Display a block of wood or ice, a balloon
filled with air, and a pot of boiling water. Illicit from students that gases
and liquids have no definite shape. Have pictures of a football, tennis ball,
basketball, and bicycle tire. Ask the students what each of these objects is
filled with (air). Illicit from students that air and water will be the same
shape of the container that holds it. Have the students observe the pot of
boiling water for about ten seconds. Point out that steam is a type of gas.
Ask them if the steam comes out of the pot in a regular pattern (no). Rap the
discussion by having the students list the properties of the different phases of

Activity: "Starchy Goop"

Using the 250ml beaker, pour cornstarch into the beaker until it is level with
the top of the beaker. Pour the cornstarch in to a mixing bowl. Mix a solution
of 110ml of water, and 4-8 drops of food color. Combine this mixture with the
cornstarch. Be sure to stir slowly, but consistently. Put a bowl of water next
to this mixture. Ask the students what should happen to a liquid mixture if you
punch it with your fist (it should splash). Demonstrate. Ask them what should
happen if you punch any liquid (it should also splash). Ask the students what
should happen if you were to punch a solid (it will not splash). Pour the
cornstarch mixture into another bowl in front of the students (for added
effect). Ask them what will happen to the cornstarch mixture (it does not
splash). Roll a piece between the palms of your hands into a ball. Ask the
students if this is a solid or a liquid. After they answer, stop rolling it and
watch what happens. Allow the students to make their own "Starchy Goop." Let
them examine and describe it. The mixture seems to have some properties of
liquids and solids.

Performance Assessment:

The assessment that I would use would be to have 10 items (solids, liquids,
and gases) in front of the students. They would be required to put them in the
proper categories. The students would also have to match the item with it's
likely particle arrangement. Each part would be worth 5 points for a total of
100 points. 95-100=Exceeds. 75-90=Meets. 70 and Below=Does Not Meet.

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