Although online courses have been a part of academia for nearly 30 years, they are still perceived as “different” than face-to-face instruction. Through in-depth interviews with four instructors, we explored how STEM faculty approach teaching asynchronous online undergraduate STEM courses. The faculty interviewed for this study viewed online courses as “not regular class[es]” and teaching those classes as “not teaching per se.” Each of the instructors had assumptions about what a classroom was and about good instruction, but even for instructors who taught online for multiple years, those assumptions remained grounded in the face-to-face environment. There is a need for greater discussion about what it means to teach in an online environment.