I've read Developing Talent in Young People (Bloom, et al, 1985), and I really like it. It's a study of about 120 world-class musicians, artists, athletes, scientists and mathematicians, focusing on their learning experience from birth to end of college (or graduate school), using both group data and individual stories to illustrate the most important factors that enabled these individuals to achieve to the limit of human abilities. Interestingly, for most of these individuals, even for mathematicians and scientists, K-12 schools didn't seem to be very relevant.
