MOSUL, Iraq – Parents in Mosul, Iraq are keeping their children home from school in a show of defiance against ISIS radicals who have overhauled the school system to fit their twisted religious views.

ISIS agents have canceled art and music classes, as well as lessons on history, literature and Christianity. They’ve also declared patriotic songs blasphemous and ripping any reference to things they don’t like out of student textbooks, the Daily Star reports.

Parents in Iraq’s second largest city have responded by ignoring the Sept. 9 start of school imposed by ISIS and keeping their children at home, opting instead to smuggle educational materials from a local market to educate their children at home.

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“What’s important to us now is that the children continue receiving knowledge correctly, even if they lose a whole academic year and an official certification,” said a man who would only give the Associated Press his nickname, Abu Hasan, out of fear of retaliation from ISIS.

“They will brainwash them and contaminate their thoughts,” he said.

According to the Daily Star:

In Mosul, schools have been presented with a new set of rules, advertised in a two-page bulletin posted on mosques, in markets and on electricity poles. The statement, dated Sept. 5, cheered “good news of the establishment of the Islamic State Education Diwan by the caliph who seeks to eliminate ignorance, to spread religious sciences and to fight the decayed curriculum.”

The new Mosul curriculum, allegedly issued by ISIS leader Abu Bakr al-Baghdadi himself, stresses that any reference to the republics of Iraq or Syria must be replaced with “Islamic State.” Pictures that violate its ultra-conservative interpretation of Islam will be ripped out of books. Anthems and lyrics that encourage love of country are now viewed as a show of “polytheism and blasphemy,” and are strictly banned.

The new curriculum even went so far as to ban Charles Darwin’s theory of evolution, although it was not previously taught in Iraqi schools.

ISIS has apparently issued a second demand for students to show up to class Tuesday, which has also been largely ignored. The radical insurgents have also required gender segregation of teachers, as opposed to only student gender segregation that previously was the norm, according to the news site.

Officials with the Education Ministry in Bagdad told the Daily Star they’re not sure what’s going on in Mosul, or other towns and cities occupied by ISIS, which currently covers roughly a third of the country.

In other areas, schools have been converted into shelters for about 1.8 million Iraqis who have fled the ISIS advance.

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“In Baghdad alone, 76 schools are occupied by displaced Iraqis, education officials said.

“All of this has a serious impact on the psychology of students,” Salama al-Hasan, spokeswoman for the Education Ministry told the Daily Star. “We want to approach this subject in a way that boosts the confidence and spirit of the students and helps them to understand what is happening in the country without instilling them with fear.”

That might be difficult, however, because a statement “put out by ISIS in Mosul ends with a chilling reminder of its willingness to use brutal force,” the Daily Star reports.

“This announcement is binding,” the statement reads. “Anyone who acts against it will face punishment.”