I was no genius either, but I was always recognized as a gifted kid. I had a private tutor when I was very young, then I studied in a pretty decent downtown Russian school and fell prey to the same old trap (which few children who are the smartest in their class and know it can avoid): zero challenge, zero socialization, zero work ethic. In my case, I had one outstanding skill, English language (well, aptitude for languages in general, but I started learning English at a very young age), so my parents naturally decided to guide me along that track and I didn't resist... but I did nothing to prepare for real life, either. I loved learning English through video games, books and, later on, Internet, and thought it would be like that in college too. During the last year of high school, after intense training, I got third prize at the regional "Olympiad" in English, and secured a free admission to a fairly prestigious university.
A year later, drained and demotivated, aghast at all the difficult and obscure subjects and skills (like advanced phonetics and medieval European literature) I was required to learn, I dropped out. Things went downhill from there on, until I got finally diagnosed with my brain condition and started getting treatment. And I still occasionally feel like a useless burnout. That lesson wasn't all that terribly painful to me, but it was a colossal waste of time. I've since read up on the perspectives of many kids who found themselves in similar situations during high school; I pity them. So many burn out or just end up underachieving. It seems that no country's educational system can currently help young people who have high IQ but not the willpower or social skills to capitalize on it.