I'm not qualified to say ADHD isn't real, but I do have some skepticisms. I read a longitudinal study that 80% of children diagnosed with ADHD and medicated were later diagnosed with depression as adults. Gee, I wonder why? Because the ADHD meds are powerful drugs you are giving to children as young as three!!! The chemical compounds of Concerta create a neuro-stimulant (to make you "focus") and a muscle relaxant (so you don't fidget). When you start anaesthetizing a child at three, don't be surprised when they are depressed by fifteen! Also, on this rant, why the hell are young children being diagnosed with ADHD? You sit them in front of 8 hours of BORING stuff at school. I'd fidget too! And I did!
I'm just saying, try working with a kid before you medicate just to make your life easier than having an energetic child.