One in five charter schools is failing and should be shut down, according to the organization representing most of the groups that authorize those charters.

"The National Association of Charter School Authorizers said 900 to 1,300 of the privately run, publicly financed schools should close because they are in the bottom 15 percent of public schools in their states," Bloomberg News reports. "The Chicago-based group's members — such as the Los Angeles Unified School District and the State University of New York — oversee more than half of the nation's 5,600 charter schools."

"In some places, accountability unfortunately has been part of the charter model in name only," said NACSA President Greg Richmond in a news release. "If charters are going to succeed in helping improve public education, accountability must go from being rhetoric to reality."

The charter school association has consistently advocated for high standards for local charter schools, but its own members continue to ignore its advice.

Indiana charter schools are among the state's lowest-performing public schools. At Fort Wayne's newest charter school, Thurgood Marshall Academy, the sponsor's defense rests on a claim that traditional public schools are criticized for making: "We serve more at-risk and disadvantaged students."

The academy was approved by the new Indiana Charter School Board, which has approved 14 new schools in less than a year.