Choose Controversies Wisely: When Teaching Scientific Argumentation, Selecting the Wrong Topic Can Impair-Rather Than Increase-Student Understanding

Articles in last summer's issue of The Science Teacher (introduced by Metz 2013), and other articles like them, tout the benefits of using scientific argumentation in teaching scientific inquiry. As science education professor Jonathan Osborne says: "Argumentation is the means that scientists use to make their case for new ideas" (2010a). Indeed, understanding scientific practice is, in part, understanding scientific argumentation. The Next Generation Science Standards (NGSS Lead States 2013) recognize "engaging in argument from evidence" as one of eight essential scientific and engineering practices. But be cautious in introducing students to scientific argumentation, especially in choosing a topic. It's tempting to choose controversial topics to teach the skill of arguing from evidence. Controversies, after all, are what people argue about. But controversial topics also pose a risk: Choosing the wrong controversial topic can result in a net loss, rather than a gain, in student understanding. So how can educators choose appropriate controversial topics? Based on our work at the National Center for Science Education (NCSE) to protect the teaching of evolution (and more recently climate change science) in public schools, we propose criteria for assessing whether a controversy is appropriate for a science classroom. Many attempts to undermine the teaching of evolution and climate change science are presented as "teaching the controversy" (Scott 2007), so we at NCSE have become particularly adept at assessing controversies, real and supposed. Our criteria, based on and expanding Scott and Branch (2003), are not arcane or complicated, and we claim no particular originality: 1. If a controversy is presented as a scientific controversy, it should be a genuine scientific controversy. Don't confuse a scientific topic that's socially controversial with a scientifically controversial topic. Climate change and evolution, for example, are politically or religiously controversial, provoking headlines and arousing passions. But they are not scientifically controversial (unlike, say, quantum gravity). Indeed, quite the contrary: The vast majority of scientists in the relevant disciplines accept climate change and evolution (on climate change, see Cook et al. 2013; on evolution, see Pew Research Center 2009). Misrepresenting a socially controversial scientific topic as scientifically controversial is committing the deadliest sin in science education: misrepresenting the science. 2. Present a scientific controversy at a level understandable by the students. There's no point, for example, in presenting contemporary debates over metabolism-first and replication-first approaches to the study of the origin of life to introductory high school biology students. While they probably can, with instruction, grasp the basic issue, expecting them to understand the detailed multidisciplinary considerations involved-much less assessing the cogency of the arguments-is unreasonable. Indeed, faced with the task of reading research papers from the primary literature, students might conclude that argumentation in science is a matter of dueling incomprehensible technicalities-which is not the intended outcome. 3. Choose scientific controversies of manageable scope. Asking students to assess the scientific arguments for or against anthropogenic climate change, for example, is unrealistic. That sort of assessment involves a major effort by multiple scientists over the course of years. For example, the Intergovernmental Panel on Climate Change's synthesis report (2007), intended as a mere summary of the evidence, involved the work of over 500 scientists. A specific controversy with a narrow focus is preferable. It's far more realistic, for example, to ask students to evaluate competing estimates of how much sea levels will rise over the next 50 years or how bird migration patterns will change over the next 100 years. …