INDIANAPOLIS (AP) – About 60 percent of Indiana’s schools are getting A or B letter grades for student progress, but about 7 percent received failing grades that could position them for state takeover if they don’t improve.

The State Board of Education approved the grades for public, charter and private schools across the state on Wednesday.

The grading system is based largely on student standardized test scores, graduation rates and college and career readiness. Critics have argued that the rules for the grades are unfair and inaccurate.

Education officials say overall, 43 schools moved up at least three letter grades.

The state carried out its first-ever takeovers last year of four public schools in Indianapolis and one in Gary after years of poor student scores.