This case study examined teacher identity development among four pre-service teacher candidates during their student teaching experience. Guided by three complementary theoretical frameworks for investigating teacher professional identities (e.g., Gee, 2000-2001; Beijaard, Meijer, & Verloop; 2004; Moje & Luke, 2009), the study focused on two closely related research questions: (a) What factors contribute to or hinder the identity formation of these four pre-service teacher candidates?; (b) How do their professional identities develop or evolve as revealed through the student teaching experience?

Four pre-service teacher candidates participated in this study. Participants were recruited from a large group of pre-service teacher candidates completing an undergraduate teacher education program at a small Midwestern liberal arts college. The data sources included interviews with the four teacher candidates, complementary interviews with their teacher mentors or supervisors, and case record artifacts and work samples. Grounded analysis of multiple data types was conducted to identify themes related to the two research questions.

Results demonstrated that multiple factors affected pre-service teachers' self-identity as a teacher, and also complexities were involved in the course of identity formation during the practicum. An examination of the data obtained revealed a total of eight themes, which can be tied directly to students' past world experiences, experiences and connections with teachers and mentors, student recognition of their own identities, student knowledge of subject matter, teaching pedagogy, teacher dispositions, classroom management, and differing tensions. Analyses of these themes highlight the various factors which contributed to these students' identity development and the sources of influence for their developing identities as aspiring teachers. The implications of these findings are discussed in light of theoretical frameworks as well as research examining identity development among all teachers, with particular emphasis on new and developing teachers.