The longitudinal analysis population of the National Education Longitudinal Study of 1988 (NELS:88) is used to produce descriptive findings about the transition to high school of eighth grade students. An overview summarizes some of the policy issues of the study and sketches the research design and samples. First, longitudinal data are used to describe some basic transitions, specifically, the proportions of the sample who changed between public and private sectors between the 8th and 10th grades or who dropped out of school. Eighth graders' perceptions of the ease of transition are summarized. Second, taking mathematics as an example, cross-sectional data are used to describe 10th grade learning and achievement, student reports of course-taking and classroom practices and emphases are summarized, and both sociodemographic and instructional correlates of mathematics achievement are examined. These examples illustrate the use of the two principal analysis populations available through the first follow-up dataset, a representative sample of 8th graders followed 2 years later as 10th graders. Eleven tables and five figures present analysis data. Further information about the availability and release schedules for NELS:88 data files is provided in four appendixes. (Author/SLD)