However, schools in cities urban fringes accounted for twice as many students as did rural schools. An additional 17.3 percent of the schools covered the upper elementary and middle grades, and offered instruction to 19.6 percent of public school students. High schools represented 18.9 percent of the schools reported, and enrolled 27.1 percent of the total number of students. About 5.3 percent of schools followed some other grade configuration, including schools that spanned all of grades kindergarten through 12 and those that were ungraded. Some 608 of these were operated directly by states or federal agencies, or had a primary role other than that of administering regular educational services.
States vary in the organization of their regular education agencies.
Hawaii and the District of Columbia each consist of a single K-12 school district. Sixteen other states also reported 100 percent of their students enrolled in comprehensive K-12 school districts. On the other hand, in Montana and Vermont less than one third of the students were served in this type of school district. These districts enrolled 5.9 percent of the nation's public school students. An additional 557 agencies could be characterized as secondary school districts, with a low grade of 7 or higher and a high grade of 12.