INDIANAPOLIS (AP) – The Democrat running against Indiana’s top schools official is calling for an independent audit of the state grades of public schools’ annual progress.

Glenda Ritz says the grades approved by the state board of education Wednesday don’t truly measure individual student achievement. She calls the measuring system “artificial.”

Ritz is challenging Republican Superintendent of Public Instruction Tony Bennett in the Nov. 6 election. Bennett says the grading system is fair.

About 60 percent of the state’s nearly 2,100 public schools received A or B letter grades for student progress in the 2011-12 school year. None of the schools is positioned for a takeover by the state because of repeatedly poor grades. Last year, the state took over five schools that had years of poor student scores.