Science

# Claims, Evidence, and Reasoning: What You’re Already Doing in Science Class—and in Everyday Life

Claims. Evidence. Reasoning. These words sound lawyerly. They feel daunting. They may even cause knots to form in the pit of your stomach.

But do they signal the need to acquire a new knowledge set for teaching science? No.

Do they signal a deep change in the way you do science with your students? Probably not.

In truth, these words—which are central to the approaches embodied in the Next Generation Science Standards (NGSS)*—are different labels for much of what you may already be doing in science class and in life.

See if this scenario rings a bell.

∞ ∞ ∞

On a rainy evening, you have dinner at a local restaurant. You leave your umbrella in a stand near the door and proceed to your table. By the time you’re ready to leave, the rain has stopped, and you forget to take your umbrella. It isn’t until the next day you realize you left it at the restaurant.

You rush back to the restaurant, and see that the umbrella stand is full. Apparently, several others have forgotten their bumbershoots as well. When you look through the umbrellas, you find yours and pull it out.

You show the umbrella to the restaurant owner and say, “This is my umbrella. I left it here last night.”

The owner says, “Are you sure? These umbrellas look pretty much alike. How do you know this one is yours?”

“Look here,” you say, pointing to the handle. “These are my initials.” To confirm the fact, you show your driver’s license to the owner.

“Okay,” says the owner. “I can see this is your umbrella because the initials on the handle match the name on your driver’s license.” The owner hands you the umbrella, and you leave the restaurant.

∞ ∞ ∞

This brief encounter is a real-world embodiment of a claims-evidence-reasoning interaction, without the terminology. Just think of it. Within the CER model, a claim answers the question, What do you know? In the scenario, you claimed that the umbrella was yours. That’s what you knew.

Evidence answers the question, How do you know that? In the scenario, your evidence was the initials on the umbrella handle which matched the name on your driver’s license. These data showed how you knew the umbrella was yours.

Reasoning is the link between the evidence and the claim. Reasoning answers the question, Why does your evidence support your claim? In the scenario, the evidence—the initials on the umbrella handle—supported your claim the umbrella was yours because they were your initials.

Both you and your students engage in this type of thinking and discourse most every day, as a matter of course. At the core, it isn’t really different from this science example offered by Assistant Professor of Education Eric Brunsell, from the University of Wisconsin–Oshkosh:

Air is matter (claim). We [his students] found that the weight of [a] ball increases each time we pumped more air into it (evidence). This shows that air has weight, one of the characteristics of matter (reasoning).
Eric Brunsell, Assistant Professor of Education at the University of Wisconsin–Oshkosh

One of our jobs as teachers is to draw on what our students already know as a way of leading them deeper into their own thinking and understanding. By embedding CER into our discourse with students and using the terms themselves, we model a thoughtful approach to learning—whether science, social studies, or literary analysis—and lead students to take ownership of the terms and processes for life.

Marjorie Frank will be presenting as part of our Fall Science Webinar Series: Innovate, Inspire, Invent—Science in Today’s Classroom.