These three users' manuals are for specific files of the High School and Beyond Study, a national longitudinal study of high school sophomores and seniors in 1980. The three files are computerized databases that are available on magnetic tape. As one component of base year data collection, information identifying twins, triplets, and some non-twin siblings was collected. The "Twins and Siblings' File Users' Manual" enables the user to examine data on 532 twin pairs, five sets of triplets, and 824 sets of data from non-twin siblings. The "User's Manual for Teacher Comment File" introduces data from teachers' responses concerning some of their students' plans after high school. The file for sophomores contains 76,560 records; the senior file contains 67,053 records. The "Friends File Users' Manual" describes the structure and use of a file of the three best friends of 58,000 survey respondents. Control card files containing both SPSS and SAS card images are available on the first two files, but not available on the third file. The student identification pages used to gather information are appended to the twins and friends manuals; the teachers' comments manual includes the questionnaire administered to teachers. (SLD)