Novice teachers' self-efficacy provides a lens through which we might understand how their self-perceptions of competence relate to teaching practices and retention. A number of cross-sectional studies have reported relations between school leader support, especially instructional leadership, and teacher self-efficacy. In this study we examine change in novice teachers' self-efficacy using growth models within the structural-equational modeling framework and relate change in self-efficacy to change in teachers' perceptions of school leader instructional support over time. Our results add support to the notion that school leaders' instructional leadership is related to teachers' self-efficacy and that instructional leadership can actually support growth in self-efficacy, at least in the case of first-year teachers.