Many national organizations support and advocate physical education's role in public health. However, only limited empirical evidence exists to support physical education’s role in public health. Physical education has the potential to benefit public health in many ways. One of the immediate benefits of physical education is the potentially large contribution to children’s daily physical activity levels. The purpose of this study was to determine the contribution of physical education to the daily physical activity levels of elementary school children based on activity group. Children wore pedometers (Walk4Life LS2500, Plainfield, IL) for 24 hours during four consecutive weekdays. Physical education step counts were assessed during 30-minute physical education classes for up to four classes. Data were collected on 548 (318 girls, 230 boys) children in grades 1-6. Based on mean DSC, children were classified into tertiles (lowest, middle, highest activity groups) to determine if physical education contributes to each group differently. Analysis of the whole group revealed that physical education contributed 17% to DSC for children in the lowest activity group, 13% for children in the middle activity group, and 10% for children in the highest activity group. For girls, physical education contributed 16% to DSC for children in the lowest activity group, 12% for children in the middle activity group, and 9% for children in the highest activity group. For boys, physical education contributed 18% to DSC for children in the lowest activity group, 13% for children in the middle activity group, and 10% for children in the highest activity group. Physical education benefits the lowest activity group the most, contributing nearly 20% of daily step counts in only one 30-minute class for children in grades 1-6. Physical education could prove to be one of the most effective interventions to increase daily physical activity levels in the least active children. The information derived from this study may aid national organizations in their pursuit to gain support for physical education’s role in public health.Keyword(s): disease prevention, health promotion, physical activity