I wonder, do such teachers think that they are somehow saving these children form their parents?

Yes:

Tessa, a 29-year-old in the Midwest who teaches 14- to 18-year-olds at a private school for students with learning impairments, says that while many of her students “simply take on the talking points and politics of their conservative parents,” this can make them especially ripe targets for full-blown radicalization and infatuation with far-right figures. “A few started listening to Joe Rogan’s podcast, which led to them reading Jordan Peterson’s books,” she says. “I think that Joe Rogan’s ideology is the biggest threat to critical thinking in the last decade.”

(...)

Here, the problem of students radicalizing online is often compounded at a social and institutional level, with far-right views being encouraged by parents and even other teachers.