CER vs ERC vs ECR: What Is the Difference?

Are these the same? Are they different? Can we really just change up the letters?

No, not really. Yes, kind of. Yes, absolutely!

As educators, we're always looking for effective ways to help our students develop critical thinking and argumentation skills. And this is especially important as we help our students work with data…so that they understand the difference between opinion and claims, between thoughts and evidence. We all want our students to be able to develop an argument or claim that is supported by evidence. And we definitely want them to be able to explain how the evidence they have selected supports their claim.

This is likely why the Claims-Evidence-Reasoning (CER) design pattern for instruction has hit the science education world by storm in the last 10+ years. 

The CER approach comes from excellent research by Katherine L McNeill and Joseph S Krajcik (check out Supporting Grade 5-8 Students in Constructing Explanations in Science: The Claim, Evidence, and Reasoning Framework for Talk and Writing). Their original framework included a second “R” for rebuttal that seems to have been mostly dropped from the approach (unfortunately).

This approach certainly intentionally mirrors well how professional scientists and textbook companies present information after it is known. First, we read about the claim from the data or “fact” to learn, then we read about what evidence supports that claim/fact, and then we read of the authors’ reasoning for how that particular set of data supports their claim/fact.

But what exactly is at the heart of each of these steps (claim, evidence, reasoning), and how do they differ? Let's dive in and explore each one in detail.

Understanding the Basics

Before we compare these steps, let's briefly define each one:

Claim

A claim is a statement that addresses the question or problem at hand. It's the conclusion that a student is trying to support or refute with the data.

Evidence

Evidence consists of data values, observations, features, or facts that support the claim. Students look for patterns, trends, or relationships in the data. This could be information from experiments, investigations, research, or reliable sources. Students thus need to carefully examine the evidence available to find which pieces of evidence they want to use as they make sense of the data. 

Reasoning

Reasoning is the logical explanation that connects the evidence to the claim. It shows how and why the evidence supports the claim. To get at reasoning students need to analyze the evidence and explain what it means (for both the data at hand and the broader context of the data). 

 Looking for more support about what goes into different parts of making sense of data across these three steps? Review our CER Capability Framework.

Exploring an Example

Let’s use an example of data from eBird.

What do you notice in this graph first?

I am going to go out on a limb and suggest that you probably noticed:

• the heights of different bars, or
• the lack of bars (gaps) in some places, or
• the clumps of bars in different time periods,

Or something else along similar lines…rather than first noticing that the annual patterns seem relatively consistent around 2 checklists reporting bald eagles a week, with an increase in mid April and early December and a decrease in the early fall.

In other words, you noticed evidence first and then with more time you thought through (or were suggested) a claim you could make about the counts based on that evidence.

If that is what we do when we are making sense of data, why do so many of existing CER graphic organizers, lesson plans, professional development hours, conference workshop sessions ask for the students to make their claim first and then share their evidence?

Well, I am not quiet sure….but let’s explore some other options for our students. 

Comparing the Frameworks

Ok, so back to the steps (minus the original Rebuttal step…which should definitely come back, but more on that later). 

Let’s think about how we can sequence these steps out and what that gets us:

1. CER (Claim, Evidence, Reasoning): A method where students start with a claim, support it with evidence, and then explain their reasoning. This approach emphasizes the claim as the first thing students are finding and subsequent steps are in support of that initial claim. As a note, this is how we write out our findings once we are done working with data. 
2. ERC (Evidence, Reasoning, Claim): An approach that begins with evidence, follows with reasoning, and concludes with a claim. This approach encourages students to avoid jumping to conclusions and instead let the evidence guide their thinking.
3. ECR (Evidence, Claim, Reasoning): A technique that starts with evidence, moves to a claim, and finishes with reasoning. This method allows students to form a preliminary conclusion based on evidence before fully explaining their reasoning.

Each of these sequences aims to help students construct strong arguments and develop scientific thinking skills. However, the order in which students approach these elements can significantly impact their learning process with the particular dataset you are working with at the moment AND seed conceptions of how to make sense of data.

 As a quick recap, let's compare the strengths and potential challenges of these different ways to sequence the necessary components of helping students construct strong arguments from evidence:

Choosing the Right Sequence for Your Classroom

When deciding which sequence to use, consider:

1. Your students' current skills and knowledge
2. The specific learning objectives of your lesson
3. The nature of the problem or question being addressed

Remember, there's no one-size-fits-all approach. You might find that different sequences work better for different topics or even different students.

 Using a graphic organizer that follows the sequence you have selected can help students visualize this process more clearly and better understand what you are asking them to accomplish as they complete their work.

 And here are some other benefits of flipping CER up with data that I can share:

• There are benefits in helping our students to see that they should not immediately be able to identify a claim from data.
• There are benefits to learning a skill in multiple ways.
• There are benefits in stressing evidence finding first before we form a claim.

We, as adults conversant in working with data, do not first see the claim. So let’s stop teaching our learners to expect that they should be able to first see it. Remembering that the bigger picture is that we are trying to get them to form arguments from evidence. And there is no one way to do that, so instead let’s provide different ways to accomplish the thinking process of developing an argument from evidence. Also, all humans are wired for confirmation bias, let’s not teach bad habits with data and graphs to perpetuate that approach to lead with the claim/conclusion and then find evidence to support your out-of-the-gate claim/conclusion.

 Need help deciding which sequence is best for your classroom? Check out our February 2020 Data Literacy 101: What can we actually claim from our data? (Science Scope 43(6): 20-26) article to find more details.

Implementing CER, ERC, or ECR in Your Classroom

Regardless of which sequence you choose, here are some tips for successful implementation:

1. Use graphic organizers: A graphic organizer can help students visualize the process and organize their thoughts.
2. Provide sentence starters: Sentence starters for each step can be especially helpful for students who struggle with writing or English language learners. The key here is making sure to change them up over time so that students don’t get into a rut with thinking it always needs to be that structure (e.g., “if…then…because…” isn’t always how the world works).
3. Offer examples: Provide examples of each step for a common data visualization to show students what a well-constructed argument looks like.
4. Practice, practice, practice: Give students multiple opportunities to use the sequence in different contexts.
5. Encourage peer review: Have students evaluate each other's work using the sequence as a guide.

To help you get started, we've created a free CER Framework downloadable resource that provides practical tools for implementing these strategies in the classroom in terms of what prompts to ask students each step of the way.

The Role of Technology in Teaching Argumentation Frameworks

In today's digital age, technology can play a crucial role in teaching and implementing these sequences:

1. Online collaboration tools: Platforms like Google Docs allow students to work together on constructing their arguments from data.
2. Digital graphic organizers: Tools like Lucidchart or Canva offer templates for creating digital graphic organizers (and make it easy to adjust up the order of the organizer based on the sequence you are using in that learning experience/activity).
3. Video creation: Students can create video presentations of their arguments, reinforcing their understanding of how to communicate their claims from data once they have explored and made sense of it.
4. Data visualization tools: For science-based arguments, tools like DataClassroom, CODAP and Tuva can help students present evidence more effectively. (Note, looking for some guidance on which tool to use? Check out our benefits and limitations of common options on the market here: https://www.dataspire.org/blog/benefits-limitations-of-different-graphing-tools 

Common Misconceptions and Pitfalls

When teaching these sequences, be aware of these common issues:

1. Confusing evidence and reasoning: Students often struggle to differentiate between these two elements. Some tips to overcome this include: having students list out multiple pieces of evidence before working on their reasoning, have students identify pieces of evidence and then work together in small groups or as a class to develop the reasoning connections, etc.
2. Weak claims: Ensure students understand that claims should be specific and arguable based on the evidence that they have on hand…not what they wish they had. Role model making tight connections between the evidence statements and claims yourself or sharing out those of others.
3. Insufficient evidence: Encourage students to provide multiple pieces of evidence to support their claims. Consider crowdsourcing evidence across the class or giving students evidence strips for a data visualization and they need to decide which align to the data and they want to use for their claim.
4. Circular reasoning: Help students avoid simply restating their claim as reasoning. This can be tricky for younger learners especially, so providing examples, sentence starters, and/or doing it together can be helpful for students to differentiate these two components.

Ignoring counterarguments: Teach students to consider and address potential counterarguments in their reasoning...early and often. Truly this may some counterintuitive but it actually strengthens their skills in making arguments when they have to argue against something.

Assessing Student Work

When evaluating student arguments using these sequences, consider:

1. The strength and clarity of the claim
2. The relevance and sufficiency of the evidence
3. The logical connection between evidence and claim in the reasoning
4. The overall coherence of the argument

The original description by Katherine McNeill and Joseph Krajcik Supporting Grade 5-8 Students in Constructing Explanations in Science: The Claim, Evidence, and Reasoning Framework for Talk and Writing) has some great examples of assessing students’ responses to the various components.

Conclusion: Empowering Students with Argumentation Skills

Whether you choose CER, ERC, or ECR, these sequences provide valuable tools for developing students' critical thinking and argumentation skills. By teaching students to construct well-reasoned arguments based on evidence, we're preparing them for success not just in science class, but in all areas of life where critical thinking is essential.

 Remember, the goal isn't just to teach a formula, but to foster a mindset of inquiry, evidence-based reasoning, and clear communication. With practice and guidance, your students will be well on their way to becoming skilled critical thinkers and communicators.

Ready to take your science instruction to the next level? Explore our comprehensive digital resources for educators!

By continuously refining our teaching methods and staying up-to-date with the latest educational research, we can inspire the next generation of critical thinkers and problem solvers. Let's work together to create a more scientifically literate society, one classroom at a time!