Since your son is 12, I would ask his opinion. If it makes his life easier, he may want to take it. If he doesn’t notice enough of an improvement to justify taking it, he may not. At 12, my daughter tried medicine but decided it wasn’t for her. I wouldn’t insist he take it unless there is a clear advantage. I would use classroom adaptations and behavior management first for a mild case. You can always try it, the medicine is not long lasting. But again, you are familiar with your situation and should trust your instincts.