Case studies are an effective way to help students understand how science works, and perhaps even more importantly, how science knowledge is constructed. Yet often when we teach the content of science, we overlook the nature of science (NOS), and in particular, how knowledge claims of science are justified (Abd-El-Khalick, Bell, and Lederman 1998; Duschl 1990). The seven examples of case studies presented here attempt to contextualize NOS concepts focused on learning about how scientific knowledge is acquired. (Contains 2 figures and 1 table.)