Charter schools are public schools that operate under contracts, or “charters,” with their states or local authorities. They are open to all children, and they don’t charge tuition.

Charter schools have more freedom to innovate than traditional public schools. In exchange for greater freedom over curriculum, pedagogy, staffing, operations, calendar and culture, charters are held accountable for meeting or exceeding rigorous academic, financial, and managerial expectations.

Minnesota passed the first charter school law in 1991, and the first charter school opened in St. Paul in 1992. Since then, 43 states and the District of Columbia have created charter legislation. States’ charter laws and regulations vary significantly.

In the 2013-14 school year, there were 6,465 charter schools nationally, serving 2.5 million students. According to the last figures released by the U.S. Department of Education, about 56% of charter schools are elementary schools, 24% are secondary schools and 20% serve both elementary and secondary students.

State-approved “authorizers” have the power to approve new charter schools and to review whether charter schools are meeting expectations.

States have different laws about who can authorize charters and how many charters can be granted. They also have different standards for whether to approve a school or renew its charter.

Authorizers can include government bodies (such as local education agencies, mayors’ offices and state boards of education), universities and not-for-profit organizations. These organizations are responsible for maintaining high standards at charter schools.

Charter schools are expected to live up to the expectations established when they were authorized. If schools aren’t succeeding, their authorizer is supposed to shut them down. Eleven states have “automatic closure laws,” under which schools not meeting standards are shut down.

In the 2013-14 school year — the most current year for which data are available — authorizers reviewed about 20% of charter schools nationally. The authorizers renewed 79% of the charters and shut down 7%. Another 14% of decisions were pending at the end of the school year when the association surveyed schools. Overall, 3.8% of all charter schools nationally were closed in the 2013-14 school year, according to the National Association of Charter School Authorizers.

Unfortunately, some failing charter schools — like failing district schools — remain open. A Fordham University study, Are Bad Schools Immortal, found that in the period studied, 72% of low-performing charters remained in operation and remained low performing after five years of persistent low performance. The same was true of 80% of district schools in the cohort studied. The study looked at more than 2,000 low-performing charter and district schools across 10 states between 2003-04 and five years later in 2008-09.

In the 2013-14 school year — the most recent year reported by the National Alliance for Public Charter Schools — more than 2.5 million students attended charter school students nationally, representing about 5% of total K-12 public school enrollment.

The number of students attending charter schools in the U.S. more than tripled in the decade leading up to the most recent year of data (2014).

Overall, about 5% of U.S. students are enrolled in charter schools, but this proportion varies from state to state.

As of 2012-13, 15 states with charter schools had enrollment less than 3%, while 16 states had charter enrollment greater than or equal to 5%. Only 2.2% of New Jersey students and 1.2% of Tennessee students were enrolled in charter schools. Among states with larger charter sectors, 7.6% of students in California and 10.4% in Colorado attended charter schools. Arizona had the highest rate of charter school enrollment, with 13.9% of public K-12 students enrolled in charter schools.

57% of charter schools are in urban communities, compared to 25% of district schools. But just as states have different charter school landscapes, urban communities do, too.

Today, there are 150 districts where at least one in every 10 public schools students is enrolled in a charter school, according to the latest data collected by the National Alliance of Public Charter Schools. There are also many urban districts with smaller shares of students enrolled in charter schools. Memphis and New York City, for example, both have 7% of students enrolled in charters, according to NAPCS.

Focusing only on urban areas, charter schools serve student populations that are similar to those served by district schools.

In 2013-14, urban charter schools served a student population that was 76.7% non-white. By comparison, the student population of urban district schools was 69.4% non-white, slightly lower than urban charters.

65% of urban charter students received free or reduced-price lunches (FRL), a common indicator of socioeconomic status. In urban district schools, 62.9% of students received free or reduced-price lunches.

50.6% of urban charters were classified as high-poverty schools (at least 75% FRL), compared to 44.3% of district schools in urban areas.

Almost all charter schools admit students without reference to test scores, essays, interviews or auditions. Any student may apply to attend a charter school. However, if too many students want to attend a school, there is a lottery to determine who is admitted.

In some cities like New Orleans and Washington, families can use an “open enrollment” system to apply to many charter schools that interest them at once. In other cities, families must apply to each school individually.

1. What's a Charter School?

2. Charter Schools from 1991 to Today

Minnesota Legislature: Resources on Minnesota Issues: Charter Schools
National Alliance of Public Charter Schools Dashboard: Students and Schools
National Center for Education Statistics at the U.S. Department of Education: Fast Facts
National Center for Education Statistics at the U.S. Department of Education: Number and enrollment of public elementary and secondary schools, by school level, type, and charter and magnet status: Selected years, 1990-91 through 2012-13

3. Charter Approval and Accountability

National Alliance for Public Charter Schools and the National Association of Charter School Authorizers: Holding Public Charter School Authorizers Accountable State Experiences and Policy Recommendations, May 2015
National Association of Charter School Authorizers: State-by-state map

4. What if Charters Don't Meet Expectations?

National Alliance of Public Charter Schools: Separating Fact & Fiction: what you need to know about charter schools
National Association of Charter School Authorizers: Infographic and other materials provided directly by the Association
David A. Stuit, Thomas B. Fordham Institute: Are Bad Schools Immortal? The Scarcity of Turnarounds and Shutdowns in Both Charter and District Sectors, December 14, 2010

5. Charter School Student Enrollment is Growing

National Alliance of Public Charter Schools Dashboard: Students
National Center for Education Statistics at the U.S. Department of Education: Number and enrollment of public elementary and secondary schools, by school level, type, and charter and magnet status: Selected years, 1990-91 through 2012-13

6. Different States Have Different Charter Landscapes

7. Different Cities Have Different Charter Landscapes

National Center for Education Statistics at the U.S. Department of Education: Number and percentage distribution of public elementary and secondary students and schools, by traditional or charter school status and selected characteristics: Selected years, 1999-2000 through 2012-13
National Alliance of Public Charter Schools: A Growing Movement: America’s Largest Charter School Communities, December 2014

8. Within Cities, Charter Students Resemble Non-charter Students

WFF calculations using 2013-14 school data obtained through US Dept. of Education, Elementary / Secondary Information System. All figures are for 2013-14 school year.

9. What if Charter Demand Exceeds Supply?

New Orleans Public School Enrollment: OneApp in the News
National Alliance for Public Charter Schools: FAQ