@sjw@neckbeard.xyz
I still remember how my biology teacher handled a delicate problem, how well she avoided pushing her personal beliefs on us.
See, there was an issue that in biology class we were taught evolution, and we also had a religion class that taught us Christianity. So of course a kid eventually asked: so who's right, science or religion?
Here's what our biology teacher told us: "my duty as your biology teacher is to teach evolution. The duty of the religion teacher is to teach you about god. I can't tell you who's right. That's for you to decide. I'm only doing my duty to teach what is in the school curriculum."
That's how a teacher is supposed to approach anything close to being political in nature. Anything less, they get fired. And when they act like this chemistry teacher acts, jail time.
This is more complex than objectivity in teaching.
I guess the attitude you describe is fine when the students are above a certain age when they can actually make that judgement, or defer it. When you're 7 or even 12, you can't consolidate this in your head. That's when parents should weigh in. And by that I don't mean come into the classroom and tell the teacher what to say/do or publicly shame the teacher. Just help their kids hold more than one thought in their heads at the same time without them exploding. Or be able to sit with an unresolved issue until they're ready to properly deal with it. I'd expect religious parents to be less good at this.
Just to clarify, I don't condone teachers actually PUSHING their beliefs on the kids like in the OP.