Proposals for school reform often focus on large and sometimes controversial systemic changes, such as charter schools, accountability standards, and changes to the way teachers are hired, fired, and compensated. Although these reforms may offer great opportunity to improve student outcomes, they may also be costly, face substantial implementation challenges, or lack definitive supporting evidence. At the same time, school boards may overlook relatively simple changes in the way schools are organized and managed that could impact student achievement in positive ways. In a new paper for The Hamilton Project, the authors present evidence on several organizational changes that could provide significant "bang for the buck" in student achievement. While simple, these changes have the potential to improve K-12 student performance substantially. To illustrate the value of making decisions about school organization based on evidence on student achievement, the authors explore three organizational changes: (1) starting schools later for middle school and high school students; (2) using K-8 schools rather than junior high or middle schools or taking other steps to minimize the disruptive transitions; and (3) assigning teachers to the same grades and subjects from year to year. The authors' proposals are not meant to transform public education radically. It may be surprising, however, that the magnitudes of the benefits of these organizational achievements relative to their costs rival the cost effectiveness of other far more sweeping reforms. The purpose of the proposal is to point out that all these small decisions about the organization of schools and school days impact student achievement, and that these types of choices need to be carefully scrutinized by school districts.