How do you successfully put a lock on a mind? You're discussing this as though sexual orientation is a choice or that it can be taught as such. That it's nurture rather than nature.

I'm sure that teaching about the existence of LGBTQ, in the context of history, prejudice, bullying, is all that's going on.

And seriously, do you really believe a teacher is going to call for that raise of hands?

Your door metaphor is nonsense.