This study examines the impact of a high ability suburban school district on the personal development of adolescents with average mental ability who had always lived in the community and attended its schools. Two groups were identified to determine the influence of academic and intellectual competition on personal development. An "average ability" group that was average on the national norms of the School and College Ability Test was compared to a "higher ability" group that was average on the suburban district's own norms. Correlation coefficients were computed between measures of personality development which consisted of the Capacity for Status, Self-Acceptance, Socialability, Achievement via Conformance, and Intellectual Efficiency scales of the California Psychological Inventory and level of intellectual ability to determine if level of ability rather than peer competition was influencing personality development. Results indicate that a lifetime of educational competition with highly intelligent peers more adversely affects the personal development of average ability females than males. (Author/HMV)