Physical education teachers have been encouraged to do their part to increase students moderate to vigorous physical activity (MVPA) while participating in physical education classes to help fight this obesity epidemic. Research involving the Sports, Play, and Active Recreation for Kids Physical Education (SPARK PE) curriculum has shown an increase in student participation patterns in classes [i.e. participation in moderate to vigorous physical activity (MVPA) for greater than 50% of class time] and increased fitness performance (i.e. walk/run and sit-ups) (Stone, McKenzie, Welk, & Booth, 1998). The purpose of this study was to examine the implementation of SPARK PE and ongoing professional development seminars on student activity time in physical education and teachers responses to the curriculum. Eleven physical education teachers (eight experimental and three control) in eight elementary schools participated in the study. Throughout the 2005-2006 year the experimental schools physical education teachers where involved in professional development opportunities (full day group in-service workshops, individual on-site visits, individual feedback on live and videotaped lessons, results of videotaped coded lessons including time students spend in activity and the amount of that time students were engaged in MVPA, and individual goal setting challenges). Data collected (mixed method) for this project extended over a six month period and included field notes from live teacher observations, video-taped lessons, formal interviews, teacher survey, lesson plans, and SPARK PE activity logs. Video-taped lessons were analyzed using three instruments: System For Observing Fitness Instruction time (SOFIT), an instruction, activity, and management time coding instrument, and the Qualitative Measures of Teaching Performance System (QMTPS). Qualitative data results indicate that the physical education teachers in this case study had a positive experience with the SPARK PE curriculum. They enjoyed the curriculum and found it easy to use, well laid out, organized, and felt that kids seemed to enjoy the lesson activities. Lesson time and equipment were barriers for implementation. Teachers stated that the professional development trainings were very useful and that the individual goal setting was beneficial to their teachings. Ongoing observation and feedback were seen as the most critical components of the professional development process that lead to teacher change. Quantitative data on student activity time (N= 639) revealed a significant increase in moderate to vigorous physical activity in lessons.Keyword(s): exercise/fitness/physical activity, obesity issues, physical education PK-12