Examined how New Zealand teachers' expectations of low- income students' achievement changed during a 6-month professional development in literacy effort, noting how those changes were sustained over a year. Pre- and post survey and interview data highlighted changes in teachers' expectations and self-efficacy. Conditions required to achieve change involved an interplay of new knowledge, unanticipated changes in students' achievement, and teachers' feelings of self-efficacy to make a difference. (SM)