More than four years after the city opened an investigation into sub-standard education at ultra-Orthodox yeshivas, and one day after it was revealed that the de Blasio administration delayed the probe for political expediency, the Department of Education has finally released the results of its inquiry.

The report found that just two of the 28 yeshivas visited by inspectors were providing the necessary secular instruction required under state law. A majority of the schools were in various stages of developing a curriculum that meets the guidelines. Five schools were shown not to be offering students any English or math lessons at all.

The high-profile report was sparked by a complaint filed in 2015 alleging that students at dozens of yeshivas in Brooklyn’s ultra-Orthodox communities are being denied a secular education. Defenders of the schools have argued it's their First Amendment right to offer students an education primarily based in Jewish studies. Others contend that there's a range of quality, and that yeshivas are moving toward a more holistic education that incorporates both secular and religious instruction.

But according to some ultra-Orthodox parents, the yeshivas may be even further from compliance than the report suggests. Several parents who spoke to Gothamist/WNYC anonymously, out of fear they'll be shunned by the community for criticizing the institutions, said the schools effectively "rigged" the results by making superficial, temporary changes before the inspections, which yeshiva administrators knew about in advance.

Some said their children got new books to display on their desks just for the inspections and were told to speak English in classes where they typically speak Yiddish.

One father said his son and his classmates should be in sixth grade, but are now being classified by their yeshivas as fifth graders, in order to mislead inspectors about the students' level of education.

Asked about the allegations, Schools Chancellor Richard Carranza said oversight would continue with subsequent visits. He pointed to a new task force that will be responsible for ensuring non-public schools meet the proposed state regulations, which have been under review for several months.

The roadmap, he said, will involve collaborating with yeshiva groups like Parents for Educational and Religious Liberty in Schools (PEARLS) to develop lesson plans in English, math, and STEM.

In a statement, a spokesperson for PEARLS claimed that the Orthodox schools outperform the city's public schools by every metric, including test scores and "more positive outcomes." But many Hasidic students do not take the Regents Examinations, and the group did not elaborate on how such "outcomes" were compared.

"As with all school systems, yeshivas always strive to improve and adopt best practices," the statement continued. "They will continue to do so."

Young Advocates For A Fair Education [YAFFED], the advocacy group that filed the original complaint four years ago, sharply criticized Mayor Bill de Blasio for dragging his feet on the investigation, allowing "a generation of students [to] graduate into adulthood without the skills needed to attain work, support families and advocate for themselves and their community."

A report released Wednesday by the Department of Investigation and the Special Commissioner of Investigation attributed the delays to the de Blasio administration's "political horse-trading," alleging that his representatives stymied the report's release in order to shore up legislative support in Albany for mayoral control of schools.

Asked about this on Friday, the mayor told WNYC's Brian Lehrer that constitutional protections and shifting state guidelines were to blame for the lengthy delay.

"There are serious limitations because of the First Amendment, and it’s something we have to balance," the mayor said. "What matters in the end is what is going to change in an imperfect reality."

The three-page DOI/SCI investigation claimed the “horse-trading” delayed the release of initial findings for a year, but did not prove the mayor personally authorized the delay. While investigators said the inaction did not amount to "criminal wrong-doing," some education experts disagree.

"This shouldn't be reduced to a mere bureaucratic conflict," David Bloomfield, a professor of education leadership, law and policy at Brooklyn College and The CUNY Graduate Center, told Gothamist. "It's about the education of ultra-Orthodox children, whose education continues to be denied through these lengthy legal and political compromises."

He added, "Even if we agree that the horse trading stinks, but is not criminal, the delay of a required investigation for political purposes is criminal."