My middle schooler has 30 minutes of phys ed at school three times a week and barely moves at home. Is this enough to keep him healthy?

Unfortunately not. In fact, health authorities recommend that all middle schoolers get at least 225 minutes of physical education per week -- more than double the amount your child gets. But he’s better off than the 30 percent of American schoolkids who get no active time at school at all. No wonder the American Academy of Pediatrics has issued a warning that the number of schools providing proper physical education for kids is at a critical low. That’s extremely sad because exercise is not just important for a child’s general health and weight control, but also for proper brain development. In fact, when kids in California took a statewide fitness test, it was discovered that those who were in better shape also did better in school. If your school doesn’t provide enough active time for your child, try to make up the shortfall with an after-school program. It doesn’t have to be a traditional sport. Your son might really like a martial arts class, for example, which will provide just as much movement without seeming like exercise.

Expert Robert S. Gotlin, D.O., is the director of Orthopaedic and Sports Rehabilitation at Beth Israel Medical Center in New York City and author of Dr. Rob’s Guide to Raising Fit Kids: A Family-Centered Approach to Achieving Optimal Health.