This case study focused on a new teacher and the transitions he experienced in progressing from a teacher education program to his first year as a math teacher in a large urban district. I situate the problem as one in which Ian may be considered at-risk for becoming a statistic of teacher turnover because of the socioeconomic, racial and cultural differences between him and his students and the structural changes he encounters at both the individual school and the larger district levels. I present three contexts or fields in which Ian evolves as a new teacher: his coteaching experience as a student teacher at City High, his work on a summer curriculum development project and his first year of teaching at Leach Learning Academy. In each field I focus on the structural changes he encounters and the ways in which he re-utilizes the practices he used successfully in previous fields. In addition, I describe the obstacles Ian faced while seeking a job in a large urban district and throughout the hiring and induction processes. The major findings of the study reveal that the teaching practices Ian developed during the coteaching experience traversed loosely bounded fields. Ian's practices of getting to know students, working with them individually and restructuring his math class led to the increased agency of his students as math learners and helped foster community. These findings contribute to an understanding of the traditional structure of teaching and learning activities in urban classrooms and how practitioners might reevaluate their practices to allow for increased collective agency for all participants in the classroom community. Implications from this study and suggestions are given specifically for teacher education programs, school district policy and both new and veteran teachers.