charter school, alternative type of American public school that, while paid for by taxes, is independent of the public-school system and relatively free from state and local regulations. A charter school has a greater degree of freedom and autonomy than the traditional public school, and students attend it by choice. Each school is granted a renewable charter, usually by a state or local board for three to five years. The aim of these schools is to increase learning opportunities and to allow for greater innovation in teaching practices. Some charter schools have a higher percentage of minority or economically disadvantaged students than traditional public schools and some specialize in a particular academic area. Charter schools are usually small, mainly urban, and vary significantly from state to state. The first charter school law was passed in Minnesota in 1991, and the first school opened there the following year; California initiated similar legislation in 1992. By 2015, more than 6,700 such schools were serving 2.9 million students in 42 states, the District of Columbia, and Puerto Rico. While many applaud the charter school movement for promoting greater choice for students and parents, it has also been criticized by those, including many teachers' unions, who are apprehensive about the possible chilling effect on other public schools, the lack of adequate supervision, and, after several years of operation, the apparently unsatisfactory performance of many of the schools.

See P. Berman, National Study of Charter Schools: Second-Year Report (1998); J. Nathan, Charter Schools: Creating Hope and Opportunity for American Education (1998); C. Finn et al., Charter Schools in Action: Renewing Public Education (2000); B. Fuller, ed., Inside Charter Schools: The Paradox of Radical Decentralization (2001).