This study of two successful first grade teachers examines the forces that guide their instructional decisions. Findings reveal the complexities of forces that influence the moment-to-moment decisions made by these teachers. Teachers repeatedly attempted to balance their desires to be student-centered while addressing state standards and implementing their schools' adopted curricula, with varying levels of success. The teachers' professional knowledge was the determining factor in that success. Levels of professional development and the professional learning communities of these two teachers and the contexts in which they were operating influenced their attention to certain forces. Findings from this study indicate that building teachers' professional knowledge through coaching and long-term professional development can improve teacher decision making