This study compared the effect of physical activity and obesity on academic achievement and was based on the premise that the health of a child has an effect on his or her ability to learn and to achieve academically. Specifically, health-related topics of inactivity and obesity were considered. The participants included 12,607 third grade children entering kindergarten for the first time during the 1998-99 school year. The data were obtained from the National Center for Educational Statistics’ Early Childhood Longitudinal Study (Third Grade), which is a national representative sample of students entering Kindergarten in 1998-99 with the latest wave of individual student, parent, teacher, administrator and school data collected on these same students in third grade. ACCESS FULL MANUSCRIPT HERE: http://cnx.org/content/m14420/latest/