As part of the standards-based accountability (SBA) system mandated under the No Child Left Behind Act (NCLB), RAND is examining how district staff, principals, and teachers are responding to SBA systems. Using two years of survey data from mathematics and science teachers on the standards-based accountability (SBA) requirements mandated by the No Child Left Behind Act, this study explores changes in teachers’ classroom content to accommodate SBA. Using two years of survey data from mathematics and science teachers on the standards-based accountability (SBA) requirements mandated by the No Child Left Behind Act, this study explores changes in teachers’ classroom content to accommodate SBA. Because aspects of SBA relate directly to the core of teaching and learning in classrooms and because changes in student achievement are likely to occur because of actions that teachers take in their classrooms, it is important to examine shifts in emphasis subjects taught, changes in the timing of topics to match the testing schedule, shifts in emphasis within a subject to reflect the material that will be tested under SBA. Results indicate that SBA policies are influencing what teachers are doing in the classroom, and that this influence is leading to an increased focus on state standards and tests. Together with the findings from other studies under this project, it is clear that there is a heavy use of test-score data, a tendency to reflect state standards in broad and narrow ways, and attention being paid to students who are most likely to show changes on the NCLB-required percent-proficient metric. Evidence surfaces on reallocation of effort toward instruction focused on tested topics toward classroom assessment methods that reflect the state test, and toward students near the proficient cut point. It is likely that certain topics, activities, and even students are receiving less attention than they would in the absence of the state test. Accountability systems can influence teacher practices, but they also raise concern about whether teachers might not only respond in ways likely to benefit student learning, but in less beneficial ways as well.