While stimulant medications can excite some children, in effect having a result that is opposite their intended result, when this occurs it is evident both at home and at school. You would notice the impact just as the folks at school do. Now, dosing can be difficult with stimulant medications, and he is likely on a dose of 18 mg. This would be a very standard dose for such a young child, and it may not be wise to exceed it at his age. It would make sense to persist with this a while longer, and if there isn't improvement perhaps employ a different medication, such as Adderall (adderrall). In addition, though, a systematic program to manage the behavior will be as critical as the medication. That is where the psychologist can be helpful to you. It isn't the face-to-face time in the office that will be the most important ingredient for your son; rather, it is the psychologist's collaboartion with you and the school in addressing the behavior that will be important. You might also want to discuss with the prescribing doctor the addition of a small amount of medicine like Clonidine or Tenex, anti-hypertensives which can be useful in children who display both ADHD and ODD.