Ritalin helps kids in the same way that caffeine helps adults. As a matter of fact, when a kid forgets to take his Ritalin in the local schools, they give him Diet Mountain Dew.
I knew a Shrink who used Caffine pills to check for ADD ADHD. What he said made sense. If the caffine pill made the kid able to sit still, concentrate, etc, then yea he was likely looking at ADD ADHD. If not? Then It was most likely another undiagnosed physical ailment doctors were missing. Please keep in mind this is not the same thing as an undisciplined child. I'm 56 now. I put away at least six Cokes a day. Caffine does not effect me in the least. I take Xanax acctually. LOL.
Many kids symptoms are being triggered by the technology of our age. In years past the triggering mechanisims weren't there. We had B&W TV, no video games, no Gameboy, and a much slower and quiter lifestyle.