In 2011, Boston Public Schools served as the primary intervention site for a federal Communities Putting Prevention to Work (CPPW) obesity prevention grant. As part of the CPPW work, Boston Public Schools implemented policies that promote an "Active School Day", including 1) increasing the quantity and quality of Physical Education provided for students, 2) increasing physical activity levels throughout the school day, and 3) implementing fitness testing in grades 4-10. The purpose of this project was to evaluate the impact of the Active School Day initiatives on Physical Education participation and school physical activity levels in K-8 grade students. Rapid-Response funding wa awarded to allow for collection of pre-intervention activity levels. Both pre- and post-data collection used accelerometer and direct observational measures.