Adderall, Ritalin, and Cylert are central nervous system stimulants.  It was once thought that they acted paradoxically in children, relaxing them rather than stimulating them.  We now know that these drugs also stimulate children, but they stimulate the parts of the brain that allow them to pay attention.

Strattera is thought to work by selectively blocking the reuptake of norepinephrine, a neurotransmitter (chemical messenger), by certain nerve cells in the brain. This increases the availability of norepinephrine, which is thought to be essential in regulating impulse control, organization and attention.