This report describes the characteristics of the 100 largest public elementary and secondary school districts in the United States and its jurisdictions. These districts are defined as the 100 largest according to the size of their student population. The information in this report was provided by state education agency officials to the National Center for Education Statistics (NCES) for inclusion in the Common Core of Data (CCD). The report uses data from the 2008-09 school year and includes student membership and staff in public schools and school districts in the 50 states and the District of Columbia, Puerto Rico, the Bureau of Indian Education, the Department of Defense dependents schools (overseas and domestic), and the four outlying areas (American Samoa, Guam, the Commonwealth of the Northern Mariana Islands, and the U.S. Virgin Islands). This report also includes graduate counts, high school dropout rates, and graduation rates for the 2007-08 school year and revenues and expenditures for fiscal year (FY) 2008. Highlights of the report include the following: (1) The 100 largest public school districts, representing less than 1 percent of all school districts in the United States and jurisdictions, were responsible for the education of 22 percent of all public school students (table 1); (2) The 100 largest public school districts employed 22 percent of the United States and jurisdictions' public school full-time-equivalent (FTE) teaching positions and contained 17 percent of all public schools and 20 percent of 2007-08 school year public high school completers (table 1); (3) The 100 largest public school districts had larger average school enrollments compared to the average for all school districts (673 vs. 514) as well as a higher median pupil/teacher ratio (15.3 vs. 15.0) (table 1); (4) The majority of students in the 100 largest school districts were Hispanic or Black (63 percent) (table 2). The percentage of students in the 100 largest school district was 26 percent, compared to 17 percent of students in all school districts, and the percentage who were Hispanic was 37 percent, compared to 22 percent of students in all school districts; (5) In FY 2008, current expenditures per pupil in the 100 largest public school districts ranged from lows of $6,363 in the Granite District, Utah, and $6,734 in the Puerto Rico Department of Education to highs of $23,298 in Boston, Massachusetts, and $22,071 in the New York City Public Schools, New York (table A-14); and (6) Three states--California, Florida, and Texas--accounted for 45 out of the 100 largest public school districts (table D-3). Appendices include: (1) Basic Tables; (2) Methodology; (3) Glossary; and (4) Supplementary Tables. (Contains 25 tables, 1 figure and 16 footnotes.) [To view the 2007-2008 report, see ED511027.].