This article examines the impact of federal, state, and local policies on the roles that elementary school teachers are asked to assume inside and outside the classroom. Through a detailed analysis of changes in teacher tasks over a 4-year period, the authors determined that role expectations increased, intensified, and expanded in four areas: instructional, institutional, collaborative, and learning. These changes had unanticipated, and often negative, consequences for teachers' relationships with students, pedagogy, and sense of professional well-being. The authors use one policy directive, differentiated instruction, to illustrate the complexity of role demands currently made of teachers, and they draw implications for policy and research. (Contains 2 tables, 2 figures and 8 notes.)