Legislation from all states employing a geographical isolation factor in calculating revenue for public school districts is summarized in this paper. The inclusion of a geographical isolation factor in a state's distribution formula for state aid is a mechanism for providing additional revenue to small schools or school districts that, because of geographical location, cannot be consolidated into more efficient units. The paper is based on national surveys completed in 1980 and 1982. It was found that four states--Nebraska, New Mexico, Pennsylvania, and Texas--have enacted legislation providing for a geographical isolation factor using an isolation criterion based on density of population. Six states--Colorado, Florida, Minnesota, Montana, Oregon, and South Dakota--include an isolation criterion based on distance or travel time to another school or school district. Eight states rely on determination by a state agency to designate schools as geographically isolated. These include Alaska, Arkansas, Georgia, Idaho, Maine, North Carolina, Utah, and Washington. Finally, it was found that two states--Florida and Minnesota--also include a geographical isolation factor based on a formula. (Author/JM)