J.F.
Hi G.,
You might want to contact the school and ask for a 504 meeting. A meeting should be held at least once a year or whenever you call one. The 504 is a legal document that follows your son through the school system (even college) and requires teachers to make accomodations for your son to help him learn. Sometimes in the transition from elementary school to middle school the communication isn't great - it's possible your son's teachers don't even know he has ADHD, is on medication, and has a 504. Sometimes the acting out can be because the work has gotten so difficult and he may not know how to get help. Simple modifications can help - if you need ideas about types of modifications, let me know and I can send you a general list of things we've tried at my school (I'm a school psychologist).
You might also talk to your peditrician about adjusting/switching medications - there are a number of options out there and some don't have depression as a side effect.
As far as at home, counseling could be helpful and you might think about setting expectations that not only does your son get things taken away for negative behavior, but he earns back privelidges and rewards for good behavior. He's old enough to understand that there is a consequence for every behavior and it's up to him whether he makes good or bad decisions.
It sounds like you've taken your son to a developmental/behavioral pediatrician for a diagnosis in the past. You could ask whoever you saw to give you suggestions as to what interventions (beyond meds) would work well for your son. You could then take those to your 504 meeting and ask that they be implemented. If you haven't seen a developmental or behavioral peditrician I'd reccommending doing so. Your pediatrician can reccommend someone (I have a list I can share also). These specialists will spend time interviewing and testing and should provide a report you can share with school. From what I've seen, they are the specialists who usually come up with that "other" diagnosis beyond the ADHD.
Good luck and let me know if I can help in any way!
J.