The Houston teacher is in violation of a policy the Texas State Board of Education passed last year banning reading materials deemed "sexually explicit, pervasively vulgar, or educationally unsuitable in public schools."
But despite being found out, she reportedly plans to continue growing her secret library.
Mary Elizabeth Castle, director of government relations for Texas Values, says this is astounding but not surprising.
"You have teachers who still want to subvert the law and are desperate to have these sexually explicit books in the classroom no matter what," she laments.
She points out that it is easy for a teacher to persuade a child to his or her thinking and to influence students instead of giving them a basic education.
"Children are impressionable, so, when you show them these sexually explicit images, or even some of the political messaging like the LGBT messaging, then they're apt to believe it, especially if these topics haven't been taught at home by their parents," Castle notes.
And that, she says, is what is happening here.
One "transgender" student who helped build the shelf says the teacher gave him a credit card to go and buy the "gay books" he thought looked interesting.
This teacher, whose name has not been released to protect her from becoming a "target for far-right-with groups," started the private book shelf when Matt Krause (R), who was a state representative at the time, sent Texas schools a list of 850 books to remove. She reportedly asked friends to help her build the library that included all of the books on the list.
Over the past two years, teachers in the state have lost their jobs or have been pressured to resign after giving students access to the titles.
Meanwhile, Castle says parents all over the country are waking up to cases like this, and they are doing what they can to protect their kids.
"Hopefully, the law will stand, and we can have this teacher face consequences for showing these inappropriate books to kids in her class," she says.