To provide a context for comparison, the study first describes changing practices and policies of the American educational system and sociodemographic changes that occurred in American society in the 1980's. This is followed by a comparison of the high school experiences of HS&B and NELS:88 sophomores, particularly differences in high school program participation. A chapter contrasts the mathematics achievement of 1980 and 1990 sophomores. NELS:88 mathematics test scores have been rescaled to permit cross-cohort comparisons for major population subgroups at the two time points. Another chapter investigates out-of-school experiences, such as participation in the high school's extracurriculum and leisure-time activities. The remaining chapters explore the self-perceptions, social image, and values of 1980 and 1990 sophomores and examine their educational and career aspirations. In most respects, the comparisons show an improvement in high school academic orientation and postsecondary expectations of the 1990 sophomore class; however, the positive changes identified are typically small or moderate, suggesting that much work needs to be done. Appended technical notes, references for text citations, tables of standard errors of measurement and sample sizes for all report population estimates, as well as an overview of HS&B and NELS:88