Ritalin - also known (when abused) as "Kiddy Cocaine" is a highly addictive substance that can that can lead to substance abuse later in the user's life.
This drug that is supposed to "focus attention" by virtue of being a Schedule II narcotic (meaning in the same class as drugs like cocaine, morphine, methamphetamine, opium and others). So, of course it focuses attention - so does speed and cocaine. It's also highly addictive, like speed or coke.
Now, I highly doubt anyone would want to give cocaine or speed to their kid. So, why would they want to give Ritalin to their child?