I had, and still have, a similar problem. Absolute top of the charts on everything. I was reading Dickens and Tolkien at the age of 7. Some of my teachers had a tendency to give me independant study in math and science because I was so far ahead of the class. In my Junior year of high school, I did independant study physics; I didn't do jack all year, but I managed to learn enough physics in one day to get a 4 on the AP test. I got into college primarily on the basis of my test scores (1560 on SAT).

For some reason, I never could really focus on the schoolwork. It really isn't very challenging or rewarding. I'm in college now, with a 2.3 GPA. Medication has helped some, but there are too many side effects, so it really isn't worth it. The only way it gets easier is if you find something to challenge yourself with. Some people can challenge themselves by competing for grades, other people just have to wait until they get out of school and get a job that interests them.

Holding you back a grade would be extremely bad if your problem is already boredom from a lack of challenges. Most people who are bored in school are diagnosed with ADD, including myself and most of my extended relatives. It is kind of a lazy meaningless diagnosis that comes with a slight stigma. It also, on the other hand, gives you a lot of advantages, if you choose to take advantage of them, such as extra time on paper assignments, tests, etc. and access to ritalin and such. These medicines will help ANYBODY with concentration, but they still won't do your work for you.

-Biscuits