NEW YORK – New York City charter schools are quickly replacing traditional public schools as the highest performing in the city, prompting school choice advocates to call on Mayor Bill de Blasio to expand access.

De Blasio, who was elected with the help of the charter school-hating United Federations of Teachers union, has resisted calls to expand access for city residents to the independently run, nonunionized public schools, which the union views as competition.

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The mayor’s position on charters is contributing to a dismal approval rating, and recent state test results will likely only make matters worse.

A new analysis finds that the number of charter schools ranking among the top 50 highest performing schools in the city has tripled since 2013, from six that year to 19 schools in 2016, the New York Daily News reports.

The report, issued by the nonprofit Families for Excellent Schools, is based on data released by the state Education Department on Friday. It shows pass rates for reading among the city’s charter school students increased from 29.3 percent in 2014-15 to 43 percent in 2015-16. Math proficiency for NYC charter school students went from 44.2 percent to 48.7 percent.

Across the city, the reading pass rate was 38 percent last year, according to the news site.

“Mayor de Blasio should support high-performing charter schools that serve our students of color and promote educational equality – not stand in their way,” Families for Excellent Schools CEO Jeremiah Kittredge said.

A recent poll shows the vast majority of New Yorkers agree with Kittredge.

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From a Wednesday New York Post editorial:

According to a poll released Tuesday by Quinnipiac University, New Yorkers believe the city should expand access to public charter schools by a 2-to-1 margin. And also by more than a 2-to-1 margin, New Yorkers believe de Blasio is actively working to prevent more children from having the opportunity to attend these life-changing schools.

It should come as no surprise, then, that residents across New York City are deeply dissatisfied with the mayor’s job performance. Just 37 percent approve of how the mayor is handling the school system, compared with 46 percent who disapprove.

The Quinnipiac poll follows the release of state test-score data that proves what parents have known for a long time: Public charter schools are providing the city’s highest-need children with a world-class education, and the mayor needs to stop standing in their way.

The news site also pointed out that the city’s charter schools are making strides in closing the achievement gap between white and minority students, unlike traditional unionized public schools.

The city’s public charter school student population is made up of 87 percent minority students, and 61 percent low-income students. The top performing K-8 school in the state of New York achieved the academic distinction with 98 percent black and Hispanic students, 75 percent of whom come from low-income families, according to the Post.

“(U)nlike the rest of the school system, public charter schools are helping to shrink the achievement gap for black and Hispanic students — who scored 73 percent higher than their peers in district schools,” the Post reports.