I am not a kid so i hesitate to give advice and can only tell u my experiences as an adult - Yes, for me I found that a certain dose could be effective for a time and then it needed to be increased - i had horrible rebound on 27 and 36 mg, but it started leveling out at 54 and 72 mg.
The key for me was that i was taking my meds too early in the day I think, so i adjusted the timing and it has helped me.
Talk to the doc and talk about timing as i do not know ur situation.
Has anyone else had this problem? My son was effective on Concerta 18mg for about 1.5 months, but now it suddenly seems not to work. All else is the same (diet, family life, etc.) We had originally moved up to 27mg in wekk #2 but the rebound was so strong that I went back down to 18mg. Let me know if sometimes the dose needs changing even after working for a while.