BOSTON - As many as one in five U.S. charter schools should be shut down because of poor academic performance, according to a group representing states, districts and universities that grant them permission to operate.
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. 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.
The announcement represents a challenge to the fast-growing charter-school movement, created as an alternative to conventional districts and operating without many of their rules. To hold the organizations accountable, states must pass new laws that would shut down poor performers, said Greg Richmond, president of the charter-school organization.
"For all the excellent charter schools, there are also many not serving students well," Richmond said from Washington in a briefing with reporters. "That's unacceptable."
The call for closing poor-performers carries special weight because it comes from an organization funded by charter-school advocates such as the Bill and Melinda Gates Foundation and the Walton Family Foundation.
About 2 million children, who make up 4 percent of public-school enrollment, attend charter schools, more than three times the number 10 years ago, according to the National Alliance for Public Charter Schools, a Washington-based nonprofit group.
After Hurricane Katrina in 2005, New Orleans turned to charter schools to overhaul public education. The schools now enroll three-quarters of the city's students, a larger share than in any other U.S. district, according to the alliance. Charter schools in Detroit and Washington educate more than 40 percent of students.
A 2010 survey by the consulting company Mathematica Policy Research compared students enrolled at charters with those who applied but weren't admitted. It found that performance was similar in reading and in math, though there were wide variations across schools. A 2009 Stanford University study found that charter students fared worse.
Poor and low-achieving students at charters showed significant gains over peers at traditional public schools, the Mathematica study found. Charters in large urban areas helped students' math achievement. Outside those regions, they had a negative effect.
In California, more students are being educated in the best charter schools than in those that should be closed, Jed Wallace, president of the California Charter Schools Association, said at the briefing.
Today's announcement follows debate about whether charter schools are weakening the finances of traditional districts, siphoning off students from the most committed families, promoting racial and economic segregation in public education, and failing to provide equal access to disabled students.
The authorizers' group is trying to police against practices that weed out lower-performing students, which can also make charter school achievement look better than it is, Richmond said.
"We want to know if games are being played," he said.
Find the latest Arizona Department of Education school scores at www.azstarnet.com/databases
This summer the Arizona Department of Education released the results of its letter-grading system for schools in the state, showing more than half of traditional public schools were labeled as B- or C-performing schools. It was the second year the state has used letter grades to rate schools.
Of the nearly 1,300 traditional schools graded across the state, 283 were awarded A's this year, compared with 2011, when 231 schools earned that designation.
In Pima County, 58 traditional public and charter schools were graded A. Of those, 42 were traditional public schools while 16 were charter schools.
Of the 315 traditional and charter schools graded in Pima County, 62 received D's, according to the state.
Of those, 38 were traditional public schools while 24 were charter schools.
No schools were given F's - a grade reserved for those schools ranked D for three consecutive years.
Arizona charter schools are faring well compared with those in other states, said the president of the state's charter school association.
"We are ahead of the curve in holding schools accountable," said Eileen B. Sigmund, president and chief executive officer of the Arizona Charter Schools Association.
"We are 17 years into this - charter schools started opening in 1995 here," Sigmund said.
Ten percent of the charter schools that were up for renewal last school year were closed by the Arizona State Board for Charter Schools, Sigmund said.
"We have work to do at the low end," she said.
"Educational achievement for students comes with great leadership and great teachers working together, and using data to inform their students," Sigmund said.
According to the association, there are 535 charter schools in the state with a student enrollment of 144,802.
A charter school receives $1,765 a year less per student in funding, compared with a student in a traditional school district, Sigmund said. The schools are publicly funded but have fewer rules and regulations to follow than traditional schools do.
About 25 percent of the state's public schools are charter schools, and 14 percent of all public-school students are enrolled in charter schools - the highest percentage for any state, and second only to Washington, D.C., according to the charter school association.