Actually, he is following the guidelines which he must follow. I would rather have a doc like that then one who just dispenses pills cause its the easiest way to go. The guidelines are here - http://www.medscape.com/viewarticle/751596?src=nl_topic
And, you can click on a link in that article to see the full text.
You didn't say how old your youngest son was or what grade he was in. If he is an intelligent kid, he may be getting by on that and so the teacher may be missing the clues. Perhaps take a look at this link to ADD and see if that fits him any better. http://www.help4adhd.org/about/what/WWK8
Many times you have to educate the teacher as to the symptoms. Those questionaires can be tricky to fill out. And, of course, there is always next years teacher or the school psychologist.
Anyway, if you haven't yet done so, I suggest you get the book - "The ADD/ ADHD Answer book," by Susan Ashley. You will find lots of ways that both you and the schools can help your children. Please post if you need any more info. Best wishes.