It’s one thing to get students to recite definitions for the states of matter. But what do they really understand? For instance, the word “gas” is confusing. My students had to stop and think whether the word was referring to a state of matter or to the liquid that is pumped into the fuel tank of a car. Likewise, when the textbook definition of “liquid” mentioned that it was a substance that could be poured and took the shape of its container, they wondered why sugar and salt weren’t considered liquids.
This Science Scope issue has lessons, background information, and teaching suggestions and SciLinks has many online resources for helping young students learn about matter. Just use the keyword matter and your grade level to see several categories of websites related to matter. Here is a sample of some that are geared to elementary grades:

• Science: Materials from the BBC is an interactive animation that could be used with a class or as a small group activity.
• Water and Ice is a three-part lesson plan from Science NetLinks
• Substances and Chemical Reactions is a lesson plan on chemical changes from Teachers Domain that also includes video clips.
• In Case of the Mystery Matter, a teacher-created Webquest, students play the role of investigators to identify and classify matter.
• Two sites, Four States of Matter and States of Matter provide information in a student-friendly style.

I was once observing a class in which the 4th-grade students were making “oobleck.” The teacher was well-organized, but she missed an opportunity to go beyond simply having the students make the substance and play with it. The article Concept-Focused Teaching describes how activities can help students learn and understand big ideas or concepts. The activity Oobleck from the Jefferson National Laboratory has some ideas for focusing students on the states of matter as they make (and play with) oobleck.
If you teach middle school, scan the table of contents in this issue for articles with some good teaching ideas for helping students who may not have a strong science background.