My problem with this mother is she's teaching her son to hate those different than him by teaching him he's better than them, when he is not. She's teaching him to not accept others. He will be in for a rude awakening when he's an adult.
It literally cost nothing to be kind and respectful of others, yet it has some of the best rewards for your soul. This mother is not doing her son any favors. I, for one, am glad they are teaching students about equality, and including trans community in that.
** might have typos as I am on my phone and I don't edit as well on my phone lol