Believe it or not, but some of the religious edge cases either don't have internet access, or don't let their kids use it. One of my kid's friends is insanely restricted in that regard, but that's a public school, so I don't doubt there's some roughly factual information that gets to them anyway.

A private school though? I can see a person being a full adult and not even suspecting they were lied to until they run across something.