Ya, it's tough to say when the appropriate age is to talk about this shit. My sister's good friend's kid is a boy who identifies as a girl. They knew when he was about 4/5 years old. He's around 9 now and always wants to wear girls clothing to school. I won't say that things are easy for him, but because there is so much awareness nowadays kids don't seem to care what he is. I can't imagine how a kid would have been treated back when I went to elementary or middle school if they had the balls (no pun intended) to publically come out.
I don't know, it's very foreign to us older folk for schools to be teaching this shit, but maybe it does more good than harm? My youngest is 7, he went through it (the education) and my oldest actually hangs out with a kid at school from time to time that switched teams. ¯\_(ツ)_/¯ I've never spoken to my kids about this stuff, it's pretty normal to them. I suppose that's the point.
At what point do the...which facilities to use questions start?
"Bla bla I don't want my boy with..."
"Bla bla I can't have my girl with...."
When you read about how terrible it can be it starts at some point. There are TONS of fathers who think a gay kid will maybe make their kid gay or sit there checking him out in the change room. It's awful.