This report updates an earlier study on educational placements of children with mental retardation, comparing data from the 1989-90 school year with the 1990-91 school year. The data indicate that regular class placements increased from 6.7 percent to 7.4 percent from 1989-90 to 1990-91. Resource room placements increased from 20.1 to 23 percent, while separate class placements decreased from 61.1 to 58.3 percent. Separate school placements decreased from 10.3 to 9.8 percent and residential facility placements decreased slightly from 1.4 to 1.1 percent. Tables indicate the percentage of students placed in regular classrooms, resource rooms, separate classes, and separate schools, for the U.S. and for individual states, for both the study years. Another table uses a formula for weighting different placements to compare states on the inclusiveness of their educational settings. The data indicate that for 1990-91: (1) Vermont, Wyoming, Idaho, Montana, and Minnesota had the highest inclusion scores; (2) New Jersey, New York, the District of Columbia, Illinois, Maryland, and Florida had the lowest inclusion scores; and (3) nine states placed fewer than one percent of students with mental retardation in regular classes. The report urges governments, advocacy organizations, and educators to continue efforts to achieve the inclusion of children with mental retardation by the year 2000. (JDD)