Louisiana is one of 30 states given a D in how it supports public schools in a survey done by a group headed by a critic of education overhauls.

The study was done by the Network for Public Education, whose president and co-founder is Diane Ravitch.

Ravitch, in a 2013 visit to Baton Rouge, blasted many of the public school changes enacted in Louisiana, including vouchers, charter schools and linking teacher evaluations to the growth of student achievement.

No state or the District of Columbia got a letter grade higher than a C.

Thirteen states got C’s, and the other eight got F’s, including Texas and Mississippi.

The top-rated states are Iowa, Nebraska and Vermont.

Each state was rated in six categories and received a composite grade.

Louisiana’s lowest mark was an F for what the group said is its failure to resist privatization of public schools.

“Charters and vouchers take the governance of schools out of the public’s hands and lead to worse inequities within the educational system as a whole,” the study says.

Charter schools are a key part of Louisiana’s education landscape, especially in New Orleans.

More than 7,000 low-income students receive vouchers — state aid to attend private schools — and the assistance was expanded statewide in 2012.

Louisiana got a D for what the group called its failure to reject high-stakes testing, which it called unreliable and invalid.

The state received a D in how it supports teachers and a D in students’ chances for success.

In other areas, the state got a C for education spending and a C for how those dollars are used.

Gov. John Bel Edwards said last week his aim is to keep state spending on public schools at current levels for the 2016-17 school year.

Edwards told a gathering hosted by the Louisiana Association of Educators that is the best education advocates can hope for amid the state’s $1.9 billion shortfall for the fiscal year that beings July 1.

Ravitch held education posts under former presidents Bill Clinton and George H.W. Bush but said she had a change of heart about public school problems after working for Bush.

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