By providing an underaged child access/directions to adult - pornographic material, for one. That in of itself should be considered disseminating indecent material to minors.
Actually that’s a good project to conduct… baiting librarians to see if they’re willing to guide children to material that is deemed indecent.
I want to assume you’re a good person so I’m going to let you know: limiting a teenager’s access to books that discuss sex in a healthy way isn’t corrupting them. Educators that want them to have access to this aren’t groomers.
Sex/sexuality are part of human nature, and every teen is developing a sense of self that will include these aspects. If they don’t have curated materials to learn from, they’ll seek these out themselves–through the internet. Porn is an awful and unhealthy way to learn about this stuff.
Outrage media will try to tell you that first grade teachers are giving instructions for sex acts, and that’s just demonstrably untrue.