During the last decade, education research and policy have generated considerable momentum behind efforts to remake teacher evaluation systems and place an effective teacher in every classroom. But schools are not simply collections of individual teachers; they are also organizations, with structures, practices, and norms that may impede or support good teaching. Could strengthening schools -- as organizations -- lead to better outcomes for teachers and students?

This study begins to address that question by examining how changes in school climate were related to changes in teacher turnover and student achievement in 278 NYC middle schools between 2008 and 2012. Drawing on teacher responses to NYC's annual School Survey, as well as student test scores, human resources data, and school administrative records, we identified four distinct and potentially malleable dimensions of middle schools' organizational environments:

1. Leadership and professional development;
2. High academic expectations for students;
3. Teacher relationships and collaboration; and
4. School safety and order.

We then examined how changes in these four dimensions over time were linked to corresponding changes in teacher turnover and student achievement. We found robust relationships between increases in all four dimensions of school climate and decreases in teacher turnover, suggesting that improving the environment in which teachers work could play an important role in reducing turnover. (The annual turnover in NYC middle schools is about 15 percent.)

We also discovered that improvements in two dimensions of school climate -- safety and academic expectations -- predicted small, but meaningful gains in students' performance on standardized math tests.

Taken together with other emerging evidence, these findings suggest that closing achievement gaps and turning around struggling schools will demand a focus on not only individual teacher effectiveness, but also the organizational effectiveness of schools. The policy brief outlines several potential areas of focus for districts that want to help schools in building healthy well-functioning organizations.

Online charter schools -- also known as virtual charters or cyber charters -- are publicly funded schools of choice that deliver student instruction via telecommunications. Today, about 200 online charter schools are operating in the United States, serving about 200,000 students at the elementary, middle, and high school grade levels. Although online instruction is increasing rapidly, there have been few studies of their operations and effects. In innovative new research funded by the Walton Family Foundation, the National Study of Online Charter Schools offers a rigorous analysis of online charter schools and their effects. Mathematica Policy Research's report provides the first nationwide data and analysis of the operations and instructional approaches of online charter schools, based on data collected in a survey completed by 127 principals of online charter schools across the country and public data from the U.S. Department of Education.

School principals are "invaluable multipliers of teaching and learning in the nation's schools," according to this report by political scientist Paul Manna, but to date it's been unclear what state policymakers could do to boost their effectiveness. Drawing from sources including the experiences of states that have focused on developing stronger principal policy, this report aims to fill that gap by offering guidance in the form of three sets of considerations for those who want to take action. The first is an appraisal of the principal's current status on the list of state priorities and the rationale for placing the principal higher on the agenda, such as the fact that principals can have a powerful effect on the classroom. The second is an examination of six policy levers that states can pull:

• Adopting principal leadership standards into state law and regulation;
• Recruiting aspiring principals into the profession;
• Approving and overseeing principal preparation programs;
• Licensing new and veteran principals;
• Supporting principals' growth with professional development; and
• Evaluating principals.

The third is an assessment of four important contextual matters for the state: its web of institutions responsible education governance and the interaction among them; its diversity of urban, suburban and rural locales; its capacity, along with the capacities of its communities, to carry out new policies; and its mandates already affecting principals.