The analysis used the concepts of cultural and social capital to provide a theoretical framework for why differential effects of parental involvement should exist across cognitive and behavioral outcomes. The data came from a representative database of 11,401 eighth graders beginning in 1988 with follow-ups occurring every 2 years thereafter. Science achievement was the measure of cognitive outcomes; truancy and dropping out of school were the measures of behavioral outcomes. Parental involvement is generally a significant factor in explaining behavioral outcomes but not cognitive outcomes. The most important factors were parent-child discussion and involvement in parent-teacher organizations. Findings also indicated that specific dimensions of involvement had greater effects for more affluent and white students, providing empirical data to support Lareau's 1989 contention that the greater levels of cultural capital possessed by members of the upper class magnify parental involvement's effect for advantaged students. The theoretical framework and associated findings also provide insight into the seemingly inconsistent findings revealed in much previous research on parent involvement and achievement. Tables, notes, appended list of variables, and 61 references (Author abstract modified)