This isn't really a "private" school thing. Schools in the middle east and in other favored Muslim territories teach religion as the main curriculum. They will teach math if it coheres with Religion. It's not anywhere close to what you, or I, in a western world regard as school structure.
There is no such thing, really, as a "private" or "Public" school in Islam, and thus Islamic studies are not subject to any regulation whatsoever.
The guy in this article says that he allows the use of these books, but then when asked about the content of those books simply states "You don't understand at all". Then backs it up counter-productively by never offering any clarification
And this is the routine answer from the American / Western Imams. They say they condemn the practices of Extremist Islam, yet they offer nothing in the lines of actually wanting to stop it. And it's not just one or two being interviewed - its CAIR, all the US islamic schools, all the imams in existence, and even assholes like Louis Farrakhan.
When approached on the evidence, or proof, of moderate Islam teaching extremist views, the only answer I hear is "No no no ... you don't understand. We are a peaceful religion. You are taking it out of context"
Then they never offer to put it in reasonable context.
I have a profound hatred of Diane Sawyer. Diane is in a hostile place, as a woman (A no no for the articles she covers). She is in Syria this week, talking to Syrians in an unveiled "Pig" manner. She asks them about extreme islam, and in one interview with the Syrian Imam, he asks:
"I do not know what you believe but..."
".. I'm an atheist"
" you're... you're a what?" <chuckle> " Oh, then this is your problem with seeing our viewpoint"
What kind of stupid ass answer is that ? It's standard scripted answer from the world of Islam, moderate or extreme. My contention is that there is no difference between moderate nor Extremism. Extreme islam allows Moderate islam to exist to give Islam a sort of "good cop, bad cop" routine wherein even if they look bad in the eyes of the infidel pigs / apes, they still have a portion of their views that can be acceptable. And when people convert to Moderate Islam (The admitted goal of Moderate Islam is STILL to take over the world) it's only a short step to go before complete Dhimmitude to Allah.
Ever see "Chronicles of Riddick" ? This is very similar.