Yes, there are solutions to childhood obesity. And there are lots of schools and communities working to implement them.

Local School Wellness Policies: Walking Their Way to Wellness

Schools are not only encouraging students to walk to school, many are also urging students to walk at school. At one Evansville, Indiana, middle school, a walking club is available for students to walk in the mornings, before classes start. Nearly 200 students participate in the morning walking club and a lunchtime club has been established at the request of students unable to participate in the morning.

… discipline had greatly improved among students who participate in the walking clubs. In addition, students were, by far, more awake and ready to focus on class time

http://www.schoolnutrition.org/Index.aspx?id=2143

These are great stories. Perhaps they will catch on.