The project uses a longitudinal and comparative research design and will generate evidence that is causal [quasi-experimental and statistical modeling]. We are doing secondary data analyses on longitudinal studies of adolescents in the USA using two data sets: 1) the Childhood and Beyond Study (CAB) and 2) the Alfred P. Sloan Study of Youth and Social Development (SSYSD). Both longitudinal datasets include extensive measures of the experiences children and adolescents have with STEM-related and non-STEM activities and courses, as well as extensive measures of self-efficacy, affective experiences, interests, educational and career aspirations, and educational course choices. The analysis and modeling of the data will make use of such techniques as structural equation modeling (SEM), hierarchical linear modeling (HLM), and person-centered techniques, such as cluster analyses, latent class analyses, and life trees.