In Chemistry, students learn about combustion reactions and their applications, such as gasoline engines in cars. Students may be asked to imagine how to maximize the output of such a combustion reaction, and how this maximization point would be determined. Teachers can explore their students’ thinking regarding these important questions using an exciting lab experiment that is also a formative assessment; the Exploding Pringles can design challenge. This open-ended formative assessment, developed by ACCT, tasks students with designing an explosion that produces the maximum boom within a Pringles container of fixed volume. By engaging students in this formative assessment activity, teachers can learn about how their students think about controlling chemical reactions in order to achieve goals. ***We have entered a video about this formative assessment in the 2020 National Science Foundation STEM for All Video Showcase, which takes place between May 5th-12th. Please view and vote for our video!***
The exploding Pringles can design challenge
In the exploding Pringles can design challenge, students are tasked with making a controlled explosion inside of an empty Pringles can in order to produce the maximum “boom.” Using the simple materials list displayed in Figure 1 below and safety precautions, students are encouraged to brainstorm and plan prior to experimentation. The activity requires a laboratory setting (with proper safety precautions) and about two hours of time; either as a single two-hour laboratory session, or as shorter laboratory sessions over several days. Students are directed to navigate the process in design cycles, in which they first brainstorm and plan what to do, then try it, and then consider the results before continuing with the next cycle. PDF documents detailing safety protocols and student handouts are available from our ChemEd X collection. The exploding Pringles can design challenge has been tested in high school chemistry classrooms in the US, and in university chemistry classes in the US, Mexico, and Costa Rica.
Figure 1: Materials available for the activity
A different kind of formative assessment
Not only is the exploding Pringles can design challenge a laboratory experience, but it is also a formative assessment that provides teachers insights into how their students think about using chemistry to control a reaction. Contrast this to typical formative assessments where students are given specific directions and cues leading them to arrive at the “right answer” for the lab. Consider the image in Figure 2 below, where a similar problem clearly cues the student that they will need to use their knowledge of mole ratios, volume calculation, and the ideal gas law based upon the information given in the problem. In this more traditional formative assessment, teachers are more likely to examine their students’ work through the lens of evaluating the correctness of student responses, in part because the problem has one correct answer. For example, teachers might notice whether a student correctly or incorrectly balanced the chemical equation for the combustion of methane, calculated the volume of the can using the correct geometric formula, or performed a calculation using the ideal gas law using the temperature and pressure values provided.
Figure 2: Image of a typical formative assessment involving a combustion reaction
Contrast this prescriptive formative assessment example with excerpts from the guiding questions from the student handout.
“...please use a few minutes to brainstorm by yourself all of the things that your team will have to THINK ABOUT to make an explosion with the maximum boom.”
“What was successful? What did you learn about making the boom?”
“What obstacles did you encounter? What did you learn about what doesn't work?”
In the exploding Pringles can design challenge, students are given the opportunity to apply their own ideas or intuitive knowledge to a chemical task. The open-endedness of the task allows students to show us what they know and reveal their thinking in a way that can’t be revealed by a more prescriptive task. In the Pringles challenge, teachers have more freedom to notice and interpret student thinking that is revealed by the task in an inferential manner. This enables us as teachers to identify and build on productive student thinking that our students demonstrate. Teachers have the ability to focus attention on identifying underlying assumptions and looking for consistency and inconsistency in student reasoning.1
As was the case with the volcano probe (described in our second blog post), the exploding Pringles can design challenge seeks to investigate students’ thinking regarding the chemical control thread of chemical thinking illustrated in Figure 3 below. This thread involves thinking about what affects chemical change, how chemical changes can be controlled, and how their effects can be controlled. Giving students opportunities to practice how chemical control is accomplished helps students make sense of critical problems in the world that chemists try to solve, including air pollution, global food production, and plastics recycling.2
Figure 3: The six threads of Chemical Thinking
This is Part 3 of a multipart series from the Assessing for Change in Chemical Thinking (ACCT) project. We, the members of ACCT (Becca, Greg, Hannah, Michael, Rob, Scott), represent a NSF-funded collaboration (NSF awards DRL-1222624 and DRL-1221494) between university researchers, graduate and postdoctoral students, and high school and middle school teachers. ACCT focuses on fostering chemical thinking in middle school, high school and undergraduate classrooms through strategic formative assessment usage. To accomplish this we develop resources, tools, and professional development for teachers of chemistry to foster students’ chemical thinking. We also study how chemistry teachers’ reasoning about formative assessment changes and how chemistry teachers shift to emphasize formative assessment as a lever for change. By working with teachers nationwide, we believe that we can help teachers reimagine the way that they think about chemistry, and develop more purposeful, productive and engaging ways of interacting with their students to help them learn. (If you would like to learn more about us, check out our prior ChemEd X blog posts, ChemEd X conference page, collection at ChemEdX, and a JChemEd article about how we collaborate). Our work focuses on Chemical Thinking and Formative Assessment as two major frameworks for professional development and research.
ACCT would love to connect with you!
As a group, we at ACCT are looking to connect with teachers nationwide to build an educator community around formative assessment and chemical thinking, as well as to share the resources that we have built and are continuing to develop. You can explore more about the ACCT project at https://www.chemedx.org/ACCT, and we welcome you to reach out to us at ACCTProject@umb.edu. Please view and vote for our video about the Pringles Can Design Challenge on the 2020 National Science Foundation STEM for All Video Showcase between May 5th-12th.
1. Murray, Stephanie; Huie, Robert; Lewis, Rebecca; Balicki, Scott; Clinchot, Michael; Banks, Gregory; Talanquer, Vicente; Sevian, Hannah, (2019). Exploring Teacher Noticing, Interpreting, and Acting in Response to Written Student Work. Manuscript submitted for publication.
2. Talanquer V., (2019), Why and how to foster chemical thinking? Unpublished manuscript.
For Laboratory Work: Please refer to the ACS Guidelines for Chemical Laboratory Safety in Secondary Schools (2016).
For Demonstrations: Please refer to the ACS Division of Chemical Education Safety Guidelines for Chemical Demonstrations.
Other Safety resources
RAMP: Recognize hazards; Assess the risks of hazards; Minimize the risks of hazards; Prepare for emergencies