Using model-evidence link diagrams to weigh alternative models in argumentation

50 S cientifically literate citizens need to understand how scientists evaluate competing explanations. Likewise, students must learn to critically evaluate the quality of scientific knowledge and weigh alternative explanations. Regrettably, high school graduates often aren’t critically evaluative about scientific topics. To help remedy that, this article presents an instruction scaffold—called a modelevidence link (MEL) diagram—designed to promote students’ ability to critically evaluate scientific arguments and deepen their understanding of fundamental science concepts. First, however, we discuss the role of critical evaluation in promoting argumentation in the science classroom.