IMPLEMENTATION: Teaching students to think like scientists.
My students have trouble explaining scientific phenomena. Why? When I probe for recall of key concepts, students are often strong. They know the answer. But other times, even if they know that vaccines prevent disease, or that ice is slippery, or that the mitochondrion is the powerhouse of the cell… they can’t tell me why or how these things happen. Given that this process of explanation and argumentation is essential to doing and learning science (Osborne 2010), I want to teach my students how to build better arguments. In the classroom, I hope to use this to make their thinking visible and to enhance our flow of learning. More broadly, I hope to weave this practice of argumentation into our activities, to develop my students into engaged and empowered problem-solvers.
Now, what makes a strong argument?
People smarter than me have broken argumentation down into three main components (McNeill 2008):
The strength of any argument, as such, depends on the strength of these components. Let’s say, for example, I ask my students How does a Bunsen burner release energy into the environment?
Students might provide answers like the following: The burner releases gas, and when you light it up with a spark, it turns into a flame. The flame is hot, and this releases energy in the form of heat.
Here’s a better response.
When we ignite a Bunsen burner, we observe light and temperatures of 1500 C emitting from the flame. We also observe the release of carbon dioxide gas and water vapor, typical products of combustion reactions. Bunsen burners release methane gas, which is a hydrocarbon that readily combusts in the presence of oxygen and heat. Thus, this release of energy must be coming from the combustion reaction, specifically the rearrangement of our reactants methane and oxygen.
The key thing here is that, in addition to having a specific claim, students also provide supporting evidence and scientific ideas. I find that when I talk with my students, the latter is often the most difficult for them. So, I want to give them scaffolds that can develop this skill. Here's mine:
Now, what makes a strong argument?
People smarter than me have broken argumentation down into three main components (McNeill 2008):
- Claim: an assertion addressing a question about a phenomenon.
- Evidence: scientific data (from lab investigations or applied research) supporting the claim.
- Reasoning: justification for the evidence (usually applying scientific concepts).
The strength of any argument, as such, depends on the strength of these components. Let’s say, for example, I ask my students How does a Bunsen burner release energy into the environment?
Students might provide answers like the following: The burner releases gas, and when you light it up with a spark, it turns into a flame. The flame is hot, and this releases energy in the form of heat.
Here’s a better response.
When we ignite a Bunsen burner, we observe light and temperatures of 1500 C emitting from the flame. We also observe the release of carbon dioxide gas and water vapor, typical products of combustion reactions. Bunsen burners release methane gas, which is a hydrocarbon that readily combusts in the presence of oxygen and heat. Thus, this release of energy must be coming from the combustion reaction, specifically the rearrangement of our reactants methane and oxygen.
The key thing here is that, in addition to having a specific claim, students also provide supporting evidence and scientific ideas. I find that when I talk with my students, the latter is often the most difficult for them. So, I want to give them scaffolds that can develop this skill. Here's mine:
THE ART OF ARGUING IN SCIENCE
In this lesson, I introduced argumentation as a scientific practice that we would be using throughout the year (and life!). This was also our first time trying out CER. Using rubrics and graphic organizers, we evaluated an example of an argument and then set out to build our own. I include an outline of the lesson below, which I adapted from Ben Meacham's work here:
- Warmup/engager: presentation of socio-scientific prompts; brainstorming arguments.
Beyond knowing scientific facts, I want my students to be able make decisions on societally relevant problems. What’s the purpose of knowing the structure of the cell, for example if students can’t defend a claim for vaccinations? This theme of socio-scientific issues is an important one for me, and for the development of scientific literacy (Sadler 2004). - Introduction of terms: Defining argumentation and why it’s important.
I really wanted to drive home that this is something that real scientists do; science happens when people build ideas, evaluate them, and refine them into working theories. It’s not the end result, the knowledge, that’s most important for us to walk away with. We want to learn the process, too. - How to build an argument: Introducing CER, offering scaffolds, and analyzing a sample argument.
In this segment, students watched a video I like this though, because they were quickly able to see why her argument was weak: her evidence did not hold up to scrutiny, and her reasoning was completely lacking. Turns out, though… they’d run into similar problems themselves. - Student practice: Using CER, students answer: Have humans evolved in the last 20,000 years?
Students worked in groups to research an answer to the above. They were encouraged to share ideas, but each had to submit their own arguments.
Claims were simple and easy. Students varied in the quality of their responses, but typically were strong at coming up with claims. This makes sense; it was a yes/no question. However, some students still provided unstructured or incorrect claims. It will be important to strengthen this skill quickly, because future prompts will be made much more complex.
Evidence was more difficult. While many students did a fine job researching and gathering supporting ideas, they were not always relevant. Often, they presented flawed or unrelated evidence. Other times, they simply rehashed scientific ideas to spin them as evidence. Not good enough. Future lessons will need to emphasize that evidence most often comes in the form of data.
Reasoning was most difficult. Students received the lowest scores here. (The lower end of the error bar here even went all the way to zero!) Very often, students would present evidence but fail to support them with any scientific ideas. Getting students to move beyond "simply reiterating data" in their arguments is a challenge, but continued support and practice should help improve this practice (Novak et al 2009).
Evidence was more difficult. While many students did a fine job researching and gathering supporting ideas, they were not always relevant. Often, they presented flawed or unrelated evidence. Other times, they simply rehashed scientific ideas to spin them as evidence. Not good enough. Future lessons will need to emphasize that evidence most often comes in the form of data.
Reasoning was most difficult. Students received the lowest scores here. (The lower end of the error bar here even went all the way to zero!) Very often, students would present evidence but fail to support them with any scientific ideas. Getting students to move beyond "simply reiterating data" in their arguments is a challenge, but continued support and practice should help improve this practice (Novak et al 2009).
Moving forward from this introduction, I made an effort to include more opportunities for argumentation throughout our curriculum. In one activity, for example, we performed collaborative discourse on whiteboards in a post-lab sense-making discussion.
Feedback from teachers and peers has also been demonstrated to be effective in learning argumentation (Novak et al 2009). By matching sample texts to CER components, students can then better understand what makes each component more rigorous. Examples of activities for practice can include the following:
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Though initial results were low, explicit scaffolds and practice have been shown to help students improve in this skill and in their scientific reasoning overall (Osborne 2010). Over the course of a month and a half, we continued to loosely practice building arguments. Finally, before closing my intervention, I had students perform a lab investigation based off of the Argumentation-Driven Inquiry (ADI) framework by Victor Sampson et al. I expound on this investigation in the following page.