Argumentation and basic logic are foundations of scientific inquiry, and thus should be foundations of science education. Students often are uninterested in formal logic, and do not understand the connection to science or society. I describe a way to engage students in the study of argumentation and to help develop student's ability to critically analyse argumentation in real-world science contexts. Following a demonstration of fallacious but persuasive argumentation, they practice logic, identifying fallacies, then construct their own arguments. (Contains 1 table.)