We will collaborate with the District to implement a subset of nutrition and physical activity policies in 12 schools using a randomized 2 x 2 research design. This will permit comparison of the potential unique and synergistic effects of these nutrition and physical activity policies on student behaviors and related health outcomes. We will follow a cohort of 5th grade students (N≈700) annually for four years to assess potential changes to student eating behaviors, physical activity levels, and BMI. We use a multi-method approach to collect data and examine predictors of these outcomes from across levels of the socio-ecological framework: student variables, family characteristics, school policies, and neighborhood features.