This paper describes a Networked Improvement Community comprised of a network of 13 states focused on improving coherence and equity in state systems of science education. Grounded in principles of improvement science adapted from healthcare, we are developing and testing resources for formative assessment in science, with the aim of developing systems where actors at every level of the education system are oriented toward a common vision for science, and where there is a common commitment to equity. The paper describes these strategies and implications of this work for district-level change efforts.