Although significant attention has been given to promoting physical activity among children, little attention has been given to the developmental process of how children learn to move or to the changing role that motor skill development plays in children's physical activity levels as they grow. In order to successfully address the obesity epidemic, it is important to understand the underlying mechanisms that can lead children and adolescents to physical activity or inactivity. This article suggests that there is a dynamic relationship between students' motor skill competence and their motivation to participate in physical activity. (Contains 1 figure.)