I think "America's Medicated Kids" is one of Louis Theroux's best documentaries. Instead of coming into the program with an axe to grind, Theroux seems surprisingly neutral about kids being diagnosed with mental illnesses. While he agrees that some kids do better with medications and need them, he also is concerned that too many kids are put on medications and diagnosed in order to make them easier to manage--when they really are just being jerky kids!
Through the course of the show, Louis visits with doctors and therapists but mostly he just hangs with families with kids who mostly have Oppositional-Defiant Disorder or similar problems that make them argumentative and practically impossible to live with for the typical family.
The bottom line is that Louis DOESN'T act like he has all the answers and truly seems concerned--and this make it a show to watch.