Hi Dawn

There are definitely others who post here, though this is not the most active of the boards at PC.

ADHD - may be a uk term (I teach in the uk). Here ADD = Attention Defecit Disorder and ADHD = Attention Deficit Hyperactivity Disorder (which is what we seem to see a lot of in school!) The hyperactivity is the difference between the two.
Hopefully someone else can give you more information than I can - I'm no expert!