Is Air Matter? Using CER to Drive Scientific Thinking
🔍 The Big Question
Once students observe that solids and liquids have mass and take up space, the next step is to ask:
“What about air? Is it matter, or something else?”
This question invites investigation and sets the stage for authentic inquiry.
Investigating Air with CER
To explore whether air is matter, guide students to:
1. Define What Data They Need
Ask:
Does air have mass?
Does air take up space?
Encourage students to brainstorm ways to test these ideas.
2. Conduct an Investigation
Example:
Weigh a basketball before and after inflating it. If the weight increases, students gather evidence that air has mass.
You might also explore how air takes up space using:
A syringe with a sealed tip
An upside-down cup in water with a dry paper towel inside
Balloons expanding when filled
What Does a Good Explanation Look Like?
Use the CER model to structure student thinking:
✅ Claim
A statement that answers the investigation question.
Example: “Air is matter.”
✅ Evidence
Data collected from the investigation.
Example: “We found that the basketball got heavier each time we added air.”
✅ Reasoning
The scientific principle or rule that explains why the evidence supports the claim.
Example: “This means air has mass, which is one property of matter.”
Pro Tip: Help students strengthen explanations by also showing that air takes up space, the second key property of matter.
Teaching CER: Tips for Success
Teaching students to write scientific explanations is a year-long process. Here’s how to support them:
🧠 Model It Explicitly
Use everyday examples first:
An Audi commercial where a girl claims her dad is a space alien.
Ask: What’s her claim? What’s the evidence? What reasoning does she use?
🧪 Anchor CER in Science
Show a short video about NASA’s Curiosity Mars Rover.
Ask: What are scientists curious about? What data will be collected? How does that data help answer their questions?
📋 Support Tools
Create an anchor chart with CER components and examples.
Use CER rubrics to review peer and teacher-created examples.
Provide worksheets where data is pre-collected and students focus on crafting CER explanations.
Extending CER Across the Curriculum
CER isn’t just for science! Use it in:
Social Studies: Historical arguments using evidence
ELA: Supporting claims with text-based evidence
Final Thoughts
Introducing students to CER helps them think like scientists. As they explore whether air is matter, they develop skills in evidence-based reasoning that will support their learning across subjects.
Keep curiosity alive, and let students lead the investigation—the best science questions start with “What if?”