My brother and sister (12 and 13) attend a Sunday class for lessons in Arabic.
This initially started as learning how to read Arabic, but soon expanded to an organisation that teaches them Islamic history (biased, of course), organises events etc.
I was chatting with an 18 year old friend who also attends and asked him if they ever spoke about the miracles of the Quran.
Apparently they do, which started a few months ago when a pupil asked "what to say when people ask why Islam is the true religion".
Now they made assignments out of it: they told them about the miracles and the students now must research and prove these miracles.
With their findings they're going to hold an event where non-muslims are invited and the 'evidence' will be presented.
The particular miracle this guy has to research is the moon splitting one. When I asked him how they brought up the evidence for this, his response was
"The teacher said that only recently NASA said that the moon in fact was split, and this is written in the Quran, which proves that muhammad was a prophet"
That's right, the same bullshit sentence that's spammed all over the web. No evidence was provided, no video, no picture, just this claim.
Now this guy has to search the web to find evidence for it, which is not hard to do considering the first 200 links you find are directed to Islamic websites.
Obviously, the websites/videos debunking this will be ignored, because that's not part of the assignment. I know this because I asked him if he believes the moon miracle, and he does, because "it's written in the Quran and NASA proved it with recent findings". *sigh*
It really bothers me that they do this, knowing my siblings (considering their age) are highly susceptible to scams like these. Having someone of higher authority already claiming this beforehand and finding out the claim is indeed true after their own research (on all the wrong sites with the wrong assumption to begin with) will only suck them deeper into the religion, making it harder to think critically in later years.
Absolutely disgusting but happens all the time all over many madrassas. Young, susceptible minds take advantaged of. That's Islam's way of saying, "Get 'em while their young".
This is a long shot but is possible to convince your rents the things they are teaching are not "Islamic" in the sense that it isn't about reading the quran in Arabic (it's useless but less mind indoctrinating) but is more about "Us Muslims Vs Those Westerners to prove them wrong" ? They try to convince them to find some other Madrassa. Only pragmatic thing I can think of. Good luck.