The purpose of this monograph was to present evidence for determining whether school-aged children were progressing toward attainment of the national physical education standards. Developed by a team of experts, the standards describe what students should know and be able to accomplish as a result of quality physical education (National Association for Sport and Physical Education, 1995, 2004). In particular, the investigators who conducted this large-scale, comprehensive study collected data over a 4-year period to assess the degree to which children were making progress toward achieving motor competence (Standard 1), regular participation in physical activity (Standard 3), and a health-enhancing level of physical fitness (Standard 4). In addition, they sought to understand participants' affective attributes and experiences in, perceptions of, and motives for engagement in physical activity and to determine whether a relationship existed between environmental access and participation. In order to examine a cross-section of individuals who represented more than a single program or individual physical education teacher, school-aged children enrolled in an 8-week physical activity program during the summer were selected as participants. A number of key findings emerged from this large-scale investigation that have implications for both the manner in which physical education is conducted and how physical activity is promoted within and outside the school setting.