INDIANAPOLIS (AP) - Critics say Ball State University hasn't done an adequate job of overseeing the charter schools it sponsors.

The Canaan Community Academy is a Ball State charter school that opened this year and is not included in the report.

A report from a charter school sponsor trade group recommends closing charters that rank in the bottom 15 percent of their state's standardized test scores. Under that standard, 10 of Ball State's 38 charter schools would be closed, The Indianapolis Star reported Sunday.

"If you are in the bottom 15 percent, there isn't much debate about whether you are succeeding with your kids," said Greg Richmond, president of the National Association of Charter School Authorizers or NACSA, which issued the report. "Nobody was approved to open a charter school saying, 'I want to be in the bottom 15 percent."'

Twenty of Ball State's charters are up for renewal by March 1, and the head of the university's charter school program, Bob Marra, said low-performing schools shouldn't be renewed.

A report from Stanford University last week said Indiana has some of the best performing charter schools in the country, but Ball State's oversight holds them back from being even better.

Ball State's tolerance for low-performing charter schools erases many of the gains other charters make and lowers the overall averages, said Stanford's Macke Raymond, one of the study's authors.

"They're not helping. The responsibility is pretty clearly on the authorizer," she said.