Despite decades of policy innovation aimed at improving school performance, the number of public schools defined as low performing in the U.S. continues to grow. Most explanations of low performance do not consider the fact that many of the country's lowest performing schools also share high rates of turnover among staff and students, or organizational instability. In this study, the author develops the theoretical underpinnings of both the concept of organizational stability and its relationship with school context and performance. The author then tests the model empirically using school level data from public schools in North Carolina. The analyses provide support for previous findings on the impact of turnover and mobility, while also contributing to a new, more nuanced, understanding of the role of school instability in helping to explain low school performance.