Focusing on national enrollment trends and projections from 1960 through 2010, this study examined two scenarios: that age-specific postsecondary participation rates will be the same in the future as they were in 1980, and secondly, that because of enrollment "catch-up" and "saturation" factors that there will be minor age-specific enrollment changes between 1980 and 2000, with rates stabilizing after that. Chapter 1 presents an overview of the study focusing on aspects as population change, education participation patterns, and projected future participation in postsecondary education from 1990 through 2010. Chapter 2 presents background information on the study including a description of the data sources and sampling procedures. Chapter 3 tracks patterns in population growth and age shifts from 1920 to 2040 and discusses racial and ethnic change. Chapter 4 addresses the historic participation trends of baby boom and other cohorts, analyzing United States enrollment and educational trend data from 1960 through 1980. The final chapter projects participation in postsecondary education of baby boom and other cohorts from 1990 through 2010. It is concluded that as baby boom cohorts reach retirement age, the dependency burden on younger adults will rise substantially and baby boomers themselves can be expected to have many concerns other than education. Six appendices include census variable definitions, interpretative notes, and supporting data. (LPT)