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Essential Science for Teachers: Physical Science

What Is Matter?: Properties and Classification of Matter Children’s Ideas About Matter

Below are common ideas children in grades K-6 have about this topic, compiled from research on children’s ideas about science. Consider what evidence might refute this idea, and why a child would be likely to believe this? Once you’ve entered all your answers you can click “printable page” at the bottom of this form to print your answers. You can also click “see possible response” for any question to see one possible response from the series content advisors.

1. “Matter” is something that is important.

The word “matter” has several different meanings. Scientists use the term matter to describe a broad range of phenomena, which are distinct from the phenomena of energy. Its scientific meaning is probably closest in meaning to the familiar words “stuff” or “material.” Until they learn this meaning in school or elsewhere, younger children may have everyday connotations for the term matter. Some examples are synonyms such as “issue, ” as in “a matter of…” or the verb form “to matter,” meaning, “to be important.”

2. All properties used to classify matter are equal.

Aristotle distinguished between “accidental” properties like color or shape, and “essential” ones like density. Essential properties are those that remain when the matter is changed in some way. Until they have more experience with essential properties, children up to age 7 might classify all round things or red things together, for example, which may result in categories that contain objects with a range of densities. Scientists would say that these kinds of classification schemes don’t have much predictive power, because they don’t necessarily tell us how matter will behave under different conditions.

3. “Cork” and “a cork” are the same thing.

A variety of objects can be made of cork, which is a form of matter. A survey of research on children’s thinking shows that the ability to distinguish matter from objects made of matter is the most important stage in children’s development of a robust, dynamic concept of matter and its properties.

4. Solids are made of many different kinds of matter, but all liquids contain water.

Children up to age 8 often adopt a “prototype,” like water with which they have lots of experience, as a component of any liquid they encounter. This idea can be challenged with a solid like wax, for example, that, when melted, turns into liquid wax, not water. In fact, all solids have a “melting point,” that is, a temperature at which they change state into a liquid.

5. Air isn’t matter.

Because it is all around them and mostly invisible, children sometimes don’t think of air as having weight and taking up space. In fact, few children have direct experience weighing air, as Siddharth was able to do in the Science Studio in the video. It is also common for children not to think of air as a gas. This is often because they have everyday connotations for gas as having an odor and/or being toxic. Once they develop a more robust definition of matter, they begin to understand that air is made of several odorless gases.

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Essential Science for Teachers: Physical Science


Produced by Harvard-Smithsonian Center for Astrophysics. 2004.
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  • ISBN: 1-57680-749-5