There has been extensive debate among scholars and practitioners concerning whether self-beliefs influence academic achievement. To address this question, findings of longitudinal studies investigating the relation between self-beliefs and achievement were synthesized using meta-analysis. Estimated effects are consistent with a small, favorable influence of positive self-beliefs on academic achievement, with an average standardized path or regression coefficient of .08 for self-beliefs as a predictor of later achievement, controlling for initial levels of achievement. Stronger effects of self-beliefs are evident when assessing self-beliefs specific to the academic domain and when measures of self-beliefs and achievement are matched by domain (e.g., same subject area). Under these conditions, the relation of self-beliefs to later achievement meets or exceeds Cohen's (1988) definition of a small effect size.

Objectives. We used nationally representative data to examine the impact of natural (or informal) mentoring relationships on health-related outcomes among older adolescents and young adults. Methods. We examined outcomes from Wave III of the National Longitudinal Study of Adolescent Health as a function of whether or not respondents reported a mentoring relationship. Logistic regression was used with control for demographic variables, previous level of functioning, and individual and environmental risk. Results. Respondents who reported a mentoring relationship were more likely to exhibit favorable outcomes relating to education/work (completing high school, college attendance, working ≥ 10 hours a week), reduced problem behavior (gang membership, hurting others in physical fights, risk taking), psychological well-being (heightened self-esteem, life satisfaction), and health (physical activity level, birth control use). However, effects of exposure to individual and environmental risk factors generally were larger in magnitude than protective effects associated with mentoring. Conclusions. These findings suggest a broad and multifaceted impact of mentoring relationships on adolescent health. However, mentoring relationships alone are not enough to meet the needs of at-risk youths and therefore should be incorporated into more comprehensive interventions.