Lack of physical education is the inadequacy of the provision and effectiveness of exercise and physical activity within modern education. More than a third of young people in grades 9-12 do not regularly engage in vigorous physical activity. Daily participation in high school physical education classes dropped from 42% in 1991 to 28% in 2003. Nearly 10 million children and adolescents in the United States ages 6–19 are considered overweight because the lack of physical education in schools. Children aged 6–11 have also more than doubled in rate of obesity over the last twenty years.