Considerable research indicates that high-stakes accountability policies have the capacity to influence language arts instruction, particularly in urban, high-needs schools where pressure to increase test scores tends to be most acute. This article utilizes Cultural Historical Activity Theory to critically examine the constraints and affordances of situating student teaching in such settings and explores how teacher educators might re-mediate preservice teachers' learning about literacy instruction accordingly. Specifically, the article examines in depth one student teacher's account of her own attempts to supplement a mandated reading program in an urban second-grade classroom and then reimagines how her practice might have looked had she been supported explicitly to manage tensions between accountability demands and robust literacy goals. The manuscript concludes with a discussion of the implications for teacher education practice in today's policy context. (Contains 2 figures.)