This paper examines the role of educational expectations in the educational attainment process. We utilize data from a variety of datasets to document and analyze the trends in educational expectations between the mid-1970s and the early 2000s. We focus on differences across racial/ethnic and socioeconomic groups and examine how young people update their expectations during high school and beyond. The results indicate that expectations rose for all students with the greatest increases among young women. Expectations have become somewhat less predictive of attainment over the past several decades but expectations remain strong predictors of attainment above and beyond other standard determinants of schooling. Interestingly, the data demonstrate that the majority (about 60 percent) of students update their expectations at least once between eighth grade and eight years post-high school. Updating appears to be based, in part, on the acquisition of new information about academic ability.