This paper will consider ways in which students are constructed as aliens in health classrooms. Creating the classroom as a setting for health promotion requires closer attention to those who make use of such space. If classrooms are places where diversity exists and is recognised, then health educators are challenged to consider how students are positioned. Too often, students have been positioned as the "other" and therefore subjected to accommodation and assimilation to dominant discourses of health. In what ways do students as "aliens in the classroom" get the opportunity to develop health literacy as a way to speak for, to or from their "other"/own space? Developing critical health literacy can help inform classroom practice in new, engaging directions. This leads, as this paper argues, to health education "praxis"--combining reflection and action for transformative purposes, for both teachers and students. Praxis offers both a philosophical starting point and a set of practical guidelines for how health teachers view and work with the aliens inhabiting the classroom.