
Last week, the National Center for Education Statistics made headlines when they released a report that showed charter schools trailing regular public schools on the 4th grade 2003 National Assessment of Educational Progress. The report, which adjusted for student characteristics, found that charter school students scored 4.7 percent lower on NAEP math test, and 4.2 percent lower on the NAEP reading test. NCES chief Mark Schneider stood by the quality of the research, but stated that it was not proper for the agency to interpret the raw data it provides, suggesting instead that it is a task best left to individual researchers. (“NCES Calls for Sticking to the Stats,” Aug. 30, 2006.)

Over the past 15 years, charter schools have become a centerpiece of the school reform movement. Since the first charter school opened in Minnesota during the 1992-93 school year, thousands of new charter schools have opened across the nation. According to the Center for Education Reform, as of 2005, there were 3,625 in operation in 40 states and the District of Columbia.
Despite their rapid growth over the past decade, charter schools still make up a modest percentage of total public schools. The District of Columbia has the highest concentration in the nation, with charter schools making up 31.5 percent of the total number of public schools, followed by Arizona with 23.3 percent. California leads the nation in number of charter schools, with 592, which account for 6.4 percent of the public schools in the state.
*Click image to view larger graphic.

Every state that has passed a law allowing charter schools, has at least one in operation. Mississippi, which opened its lone charter school in 1998 has the lowest concentration of charter schools with 0.1 percent.
To find out more about charter schools in the 50 states and the District of Columbia, access the Education Counts database.