Just before the holiday break I had a bit of a revelation. I’d heard of this “Claim, Evidence, Reasoning” thing (resources on this at the end of this post) as a framework for writing scientific arguments, and I was hooked from the start. This was it! This is how I get my students to stop staring at their papers blankly when I say “justify your answer.” Or flail about including as many fancy-sounding vocabulary words as possible in a desperate attempt to get something, anything right. I dug through a ton of resources, read a few papers, and I was set!
Before you go further, if you’re not at all familiar with what I’m talking about, take some time to read up. A quick Google search will turn up lots of great stuff. This example is an excellent start.
My original vision for using the CER framework was in writing good conclusions to lab reports. And it’s a fantastic tool for that! But that’s only one way to use it. It was especially problematic for me because I wanted to offer my students opportunities to practice, but that would require doing a lab and having them write a paragraph-length conclusion. And then I’d have to grade them. I did this for one lab. Some kids got it, most didn’t, and I didn’t have the energy to try again. Eventually, it dawned on me what I was doing wrong.
Additionally, I think that CER is the way to go about preparing AP Physics 1 and 2 students for the new writing-focused section of the Free-Response questions.
CER isn’t just for elaborate conclusion writing. It’s for anything that ends with “justify your answer” or “explain your reasoning” or some other clever iteration of the same thing we always want students to do: tell me why.
Disclaimer: the idea presented below was shamelessly ripped from Eric Brunsell‘s Edutopia article Designing Science Inquiry: Claim + Evidence + Reasoning = Explanation. You can find the slides I used here, and here is the graphic organizer that I use. The organizer is a PowerPoint slide, but it prints like a regular sheet of paper.
I start off with some definitions that I pieced together through a few minutes of Googling. I’m not sure how useful copying definitions is for the students, but it feels like the right thing to start with. And it probably doesn’t hurt, so why not?
I spend a few minutes talking about each one, mostly to fill the silence while they dutifully copy. I answer “what’s olfactory?” a few times, too. Next, the video:
First off, the little girl is adorable. And the commercial is rather amusing, which helps with engaging students. Most importantly, as odd as it may sound, it’s very straightforward. She states that she has evidence and then lists off what that evidence is. Very little room for interpretation here. This is nice because it allows the discussion to focus on what I feel is actually the most difficult part of CER: the reasoning. And this is where student creativity can shine.
Here Comes the Hard Part
Why is the reasoning difficult? Because it is generated solely by the student. It requires the student to connect the dots from evidence to claim. The best example I saw of this creativity was from this piece of evidence that the little girl provides:
He says he’s from Albuquerque? I’m not buying it.
My handout only has spaces for 4 pieces of evidence, but she presents 5. The Albuquerque one was the one that was left off the most often. To be perfectly honest, I didn’t consider it a viable piece of evidence until my students chimed in. I love it when I’m wrong! Here are some responses:
- It’s a very strange sounding name for a city. She thought he made it up.
- She’s never heard of this place before, so it couldn’t exist.
- He slipped and spoke some of his “weird language.”
My favorite bit of reasoning was in response to the He speaks a weird language piece of evidence: no other human language requires water to be spoken.
Making a claim is easy. Students do this all the time. Finding evidence to support it can also be easy. Just throw some numbers and vocab words out there and see what sticks. The true test of understanding is if the student can link it together with reasoning. Another reason why this video is a great start to the topic is because coming up with reasoning for the evidence presented is still fairly simple. It illustrates the idea to the students without imposing too much of a cognitive demand.
The reasoning is, in my opinion, the most critical part of the CER structure. It’s the glue that holds it all together. And, despite the relative ease of the introductory example, I maintain that it’s the most difficult part.
And Now, a Physics Example
I formally introduced CER in the middle of my energy unit, so I used this as a follow-up example.
In both my AP and College-Prep classes, students quickly and easily identified that the car slowed down (claim) because it lost kinetic energy (evidence). However, I was awash with blank faces when I asked “So, class, who wants to share their reasoning?”
It’s actually quite difficult for a student in an intro physics class to answer the seemingly simple question of “Why does an object slow down if it loses kinetic energy?”
Many students said “well, it’s going uphill (a claim unto itself) because it’s losing gravitational potential energy (evidence).” To which my response was “How do you know the driver doesn’t have their foot on the gas pedal? You can speed up and go up a hill at the same time, ya know…”
I was satisfied with one of two responses:
- Kinetic energy is the energy of motion. If kinetic energy decreases, then the motion decreases. – I was less a fan of this because of how vague “motion decreases” is.
- The equation for kinetic energy is (1/2)mv^2. If you plug in a bigger number for v, then the kinetic energy increases. If you plug in a smaller number for v, then kinetic energy goes down. – I like this response much better because it references an equation in a conceptual way.
To help students see the connection to the equation, I wrote it up on the board and asked a few leading questions.
- Which of these variables are constant? Which changes?
- Think about how each variable “interacts” mathematically. Are they added, multiplied, divided by, exponentiated, something else?
- Imagine you are making up numbers to plug into each of these variables. Now imagine plugging in a larger number, think about what that means physically, and figure out how that affects the kinetic energy. Do the same for a smaller number.
This was also the first time that I’d asked students to think about equations conceptually in this way (which I need to do more of!), so they struggled for a bit. When I asked them to do the same for question 2, it went much more smoothly.
While the introduction to CER went exceptionally well, my students still need lots of practice. I’m going to spend the next week or so doing warm ups that are exclusively this. One way to scaffold this is to simply ask them to write C: E: R: on three lines on their paper, and to fill in the blanks.
Another great candidate for using CER is the nTIPERS book. It’s swimming in problems begging to have CER slapped on them.
This also ties into a new framework that my colleague came up with for writing learning goals. I’m dividing them up by qualitative, quantitative, graph/data interpretation, and lab.
Who knows if this will work out at all as I haven’t tried any of it yet, but it’s nice that the CER thing seems to work well with it.
- A collection of excellent blog posts on Always Formative.
- Inquiry and Scientific Explanations.
- Claims-Evidence-Reasoning: Supporting Student’s Writing.
- Supporting All Students in Writing Scientific Arguments.
- Everything on this page.
I’m loving how this is turning out. My students are rockin’ it so far!