Struggling with this diagnosis

My child has been labeled ADHD by the psychologist at his elementary school. This diagnosis was seconded by a psychologist of our choosing. I am a big believer of not using medication on MY child (do what is best for your child). Up until the end of first grade, nobody mentioned ADHD, but more than a few people mentioned gifted. We've had some tough days the past week but today, my boy did fantastic in school. What was the change? you ask. Motivation. He knew he had a box from his Grandpa sitting in my room that he could have if he had a good day. Now, you tell me, can a child with ADHD just decide to behave because it suits his purposes? I highly doubt it. It would be like someone with a broken leg deciding that it wasn't broken today because they wanted to go the zoo. I've struggled with the concept of ADHD since I was in college and did a huge research paper for a psych class I was in. I personally believe that it is completely over diagnosed, especially by school personnel. I find it interesting that so many more boys are "diagnosed" with this disorder than girls. I attribute this the fact that boys act like, well, like boys. The are generally loud, boisterous, always on the go and dislike authority. Most boys I know would rather take apart a motor than read about how to do so. Most boys I know are always running, jumping and taking risks. Most boys I know will eventually challenge authority. Kind of like the young males in a pride of lions. Or the young stallions in a herd of wild horses. It's why they get kicked out of the pride or herd. But it serves a purpose. If they didn't challenge the leader, who would lead when the leader is no longer capable? Who would take over and allow the pride or herd to continue it's existence? That's what our boys are supposed to do. The ones that are challenging the leaders are the ones that will eventually lead. Unless they get stamped out by the school system. Because the school doesn't really care about future leaders. The school cares about conformance today. But if all we produce is boys who conform, who will lead us tomorrow?