Spending as much time outside of school as in school, gifted youth are affected by non-school aspects including parents, other family members, peers, mentors, mathematics competitions and camp participations. These influences have been known to shape children's intellectual development, academic achievement, interests, and eventually college and career choices. From interviews with five former Olympians from Korea to identify out-of-school influences on their academic achievement and development, we discovered, in addition to confirmation of previously identified factors, additional sources of positive influence seldom previously mentioned and more common to Korean culture were gleaned - mathematics workbooks and Ha-Gwon. The findings of this study are informative for teachers and parents who are interested in development of gifted youth in providing ways to accommodate their special needs and in showing how they can carefully individualize those sources to be positively affecting intellectual development as well as academic achievement.