As researchers and teachers, we have particular beliefs about the world and how it works, and about classrooms and how they work. Borg notes that "beliefs colour memories with their evaluation and judgment, and serve to frame our understanding of events" (Borg, 2001, p. 187). When already qualified teachers, in a TESOL graduate program, undertake their compulsory supervised practice teaching in TESOL settings, they are confronted with just how different their new discipline is. Using former students' reflections on their placements as data, the research project reported in this article aimed to uncover what novice ESL teachers experience during the practicum. What do they have to learn in order to experience success in the ESL classroom? What do they have to unlearn? Some of the reasons for the steep learning curve that the participants noted were that mainstream pedagogy did not just transfer into the ESL context, that visuals were very important, and that they had to learn ways of gauging students' language levels.