As education-reform activists prepare to demonstrate at New York’s City Hall on Wednesday, a massive grade-fraud scandal has been exposed in America’s largest public-school system. SOS NYC, an organization that fights the under-education of Gotham’s children, released middle-school ratings using its nascent School Grade Fraud Index (SGFI). The Index divides the percentage of a school’s students who pass their math classes by the percentage of students who pass their New York State math tests. The higher the Index, the greater the fraud. If 100 percent of a middle school’s students pass their math classes and 100 percent of students also pass the state math test, the school would have an SGFI of 1.0. Conversely, if 100 percent of students passed their math classes, but only 1 percent of students passed the state exam, the school’s Index would be 100.

SOS NYC found one Bronx middle school, P.S/I.S. 224, in which 93.5 percent of students passed their math classes, but only 2 percent passed the state math exam. This yielded an SGFI of 46.75.

New York’s five worst schools, by this measure, include P.S./I.S. 224, three others in the Bronx, and one in Manhattan:

The Bronx’s Academy for College Preparation had a math-class-pass rate of 90 percent, but only 4 percent passed the state math test, yielding an SGFI of 22.5.

The Bronx’s East Fordham Academy for the Arts: Class rate – 80.3 percent, test rate – 4 percent, SGFI – 20.08.

The Bronx’s Academy of Public Relations: Class rate – 97 percent, test rate – 5 percent, SGFI – 19.4.

Eagle Academy for Young Men of Harlem: Class rate – 93.9 percent, test rate – 5 percent, SGFI – 18.78.

Two dozen schools have SGFIs above 10.0. The best of these is Brooklyn’s P.S. 308: Class rate – 70.5 percent, test rate – 7 percent – SGFI 10.07.

Campuses with the highest SGFI scores are concentrated in The Bronx, Upper Manhattan, Central Brooklyn, and Southern Queens — all predominately black and Hispanic communities. SOS NYC’s 3-D heat map represents each middle school’s fraud index with a colored bar. The redder and taller the bar, the higher the index. Thus, a map of the Bronx is clogged with statistical red skyscrapers.

Thousands of NYC students are graduating high school without the academic skills to be “college ready.” A majority of Gotham’s eighth graders lack the foundational education to study a rigorous high-school curriculum. Bronx ninth graders try to learn math from Dan Fendel’s Interactive Mathematics Program Year 1. It contains only one equation and zero “solve for X” problems. But this textbook is stuffed with social-justice propaganda. One homework assignment involves graphing Native American Indian acreage versus how much time it took to break treaties and force these indigenous people from their land. Another assignment explains how to divide supplies with a family of escaped slaves.

“How much longer are we going to permit the NYC Department of Education and NYC Mayor to pull the wool over our eyes when it comes to the education of our children?” demanded activist Katherine James, a three-term former school board member from southern Queens, where grade fraud is pervasive. Her recent e-mail to fellow education reformers included this battle cry: “Join with others to take the crucial action required to correct this plague rampant in our public schools. Do not permit our children and families to continue to be victims of fraudulent reports perpetrated by government leaders in NYC. Save Our Schools/Save Our Children! End the School-to-Riker’s-Island Pipeline Now!” (Riker’s Island is the Big Apple’s largest local prison.)

Little if any of this has registered with Mayor Bill de Blasio (D-New York). He has been busy lately, running for president. He had breakfast in April with a whopping seven Democrat leaders in Pahrump, Nevada. Earlier, he told voters in Las Vegas that he wants a “program of actual redistribution which includes much heavier taxes on the wealthy.”

Too bad de Blasio doesn’t move permanently into Sin City’s New York-New York Hotel & Casino. That might stymie his anti-meritocratic bid to scrap the Specialized High Schools Admissions Test (SHSAT) for Bronx Science, Brooklyn Tech, Stuyvesant, and other high-performance Specialized High Schools. Ironically, de Blasio has proposed admission standards that rely heavily on middle-school grades. Since few children on campuses with rampant grade fraud enter these beacons of opportunity, one wonders if de Blasio is changing their admission criteria to cover up his failures nearly everywhere else.

De Blasio also is embroiled in scandal over his mismanagement of the New York City Housing Authority (NYCHA). In January, U.S. Housing and Urban Development Secretary Ben Carson ordered a U.S. Court monitor to settle federal litigation over the quixotic presidential aspirant’s spectacularly deceitful abuse of NYCHA’s 392,259 public-housing residents.

This suit was triggered by de Blasio’s bogus “lead-paint inspections.” With de Blasio at the helm, HUD ordered NYC to test public-housing units for lead. NYC failed to conduct those tests, then lied to Washington about the tests it never performed. If de Blasio used the same fraud he is pulling in NYC’s schools, he could have abandoned traditional lead tests and, instead, allowed inspectors to give buildings passing grades, despite their failing marks.

De Blasio’s vicious fraud against the children of NYCHA will have lifelong consequences. As the de Blasio administration’s analysis eventually conceded, “1,160 children living in public housing have tested positive for lead poisoning since 2012,” the New York Post reported. “NYCHA has come under scrutiny since [2017], when it was revealed that the agency failed to conduct required lead inspections since 2013 (the year de Blasio was elected) and lied to the feds about it.” The Post added, “Since then, Mayor de Blasio’s Health Department has repeatedly revised its figures on lead-poisoning cases, previously citing just 820 positive tests and, before that, acknowledging a mere 19.” If this is how Gotham’s slumlord-in-chief treats overwhelmingly Democrat, low-income, blacks and Hispanics — his political base — what’s in store for his enemies?

Rather than improve the health and education of local children, de Blasio just launched a jihad against glass-and-steel skyscrapers, all to battle ever-elusive “global warming.” This boneheaded move would be like the mayor of Venice banning canals, filling them with cement, and converting them into bike lanes.

“The power of [mayoral control] is, everyone here, and all the parents of New York City, get to hold me accountable,” de Blasio told state lawmakers in Albany in February, while lobbying to extend his grip on local schools. For once, the “Dope from Park Slope” got it right. City parents need to hold him accountable for his epic fails on education. Alas, most parents are unaware of their children’s under-education until it’s too late, due to fraudulent report cards. De Blasio and Richard Carranza, his equity obsessed De-education Chancellor, must end this duplicity so city parents can keep their feet to the fire. Maybe then, New York City’s government-school students will have a fair shot at the American Dream.

Deroy Murdock is a Manhattan-based Fox News contributor and contributing editor with National Review Online. Charles Vavruska is a New York City-based parent activist and evangelist for the local Specialized High School Admissions Test.