This study was begun in the Fall of 1985 to determine the long-term effects of retention in one of the six COOR Intermediate School District Areas (Roscommon, Michigan). The major focus is on academic achievement as measured by the California Achievement (CA) Test, which has been given to every kindergarten through eighth grade student in the Areas since 1980. Every student in the district was studied with the exception of students in grade 12. The district studied is comprised of two elementary schools, two middle schools, and one high school. The total population consisted of 2,800 students. Data analyzed included the following: (1) sex; (2) age; (3) retention; (4) free or reduced lunch; (5) CA Test information; (6) special education; (7) chapter services; and (8) ancillary information believed to be relevant. Conclusions include the following: (1) males are more likely to be retained and double retained than females; (2) retained males are more likely to receive special education services than females; (3) analysis of the CA scores of 166 students retained in the first, second, and third grades indicates that there is little long-term benefit from retention; (4) retained males and females do not achieve differently after retention; (5) non-retained students perform academically better than retained students; (6) non-retained students perform academically better on the average over time than do retained students; and (7) retained students are more likely to be economically disadvantaged. The appendix is comprised of nine statistical data on nine tables and 11 graphs. (FMW)