First thing: Katherine Stewart has many books. One of them is The Good News Clubs. Buy it. Read it. Trust me on this.
Good New Clubs are something I did a lot of research on when I was with the SSA. At one point I even called their national HQ as a sympathetic parent. The person with whom I was speaking flat out told me that most people come to Christ between the ages of 4-14 (as Doug Stanhope puts it, while they’re still Santa Claus eligible), which is why we need to be evangelizing to them in their elementary and other public schools.
What they try and do is have older students evangelize to younger students right after the end-of-school bell in order to give the impression that this is school-taught material. This can, and does, have a powerful effect on children. Katherine Stewart gives several examples of children coming home and saying to their parents that you go to hell if you don’t believe in Jesus, and it must be true because they taught it in school.
From the manual of the GNC:
“King Saul should’ve been willing to obey god completely, but he disobeyed by keeping the king alive.” Lesson: partly disobeying is still disobeying. Teaching Statement: having the children repeatedly shout: “God will help you obey.”
Also, at one point one of the higher ups in the their ministry in charge of proselytizing to Hispanic kids said “Don’t disparage the Catholic Church, at least not in the beginning.” Let there be no doubt: evangelists like this are about manipulating, not about presenting the facts.
In some cases, teachers at the schools are aiding with the deception.