In any case, appropriateness is a valid concern. But the best qualified people to address that concern are educational professionals like librarians and English teachers.
According to a study conducted around 2022, about 1 in 10 students experience some form of educator sexual misconduct by the time they graduate high school. Specifically, the study found about 11.7% of students reported sexual misconduct by educators, which was an increase from the 9.6% estimated in the 2004 study which means things have gotten worse, not better.
So, no, I do not believe that the best qualified people to address the appropriateness of books for children are educators or librarians.
Additionally, while teachers aren't as far to the left as some conservative media would have one believe, they do tend to be roughly 10% more left of center than the general population which means they are not fully representative of the populations they serve.
The best qualified people to address the appropriateness of book for children are the parents.
Without being able to examine the methodology of the two studies, it's difficult to judge the accuracy of the conclusions. It is worth noting that the vast majority of the misconduct took the form of sexual comments. Depending on how the information was collected and whether or not the study used a very specific definition of sexual comment, how much time had passed since the alleged comment, whether or not the context of the comment was clear, etc. all make a difference.
I'm not suggesting that sexual comments are ever appropriate in the classroom. I am suggesting that some adolescents will find innuendo where none was intended, that eyewitness accounts become less accurate over time, and that "sexual comment" could conceivably be applied to something like a discussion of adultery in
Scarlet Letter--the subject matter is sexual, after all.
I'm not just hair-splitting here. As a union rep, I was involved in a number of student complaints against teachers. Fortunately, none of them were sexual, but they do illustrate the problems with students complaints in general. Often, students cited statements or behavior that closer investigation revealed were partially or wholly inaccurate. My favorite example is one in which a teacher tapped a student with a rolled piece of paper to get her attention. The student claimed that the teacher had hit her. Every single student in the classroom said something like, "No, he just tapped her. There was no hitting." The teacher was rightly exonerated. But had this student been participating in a study of physical violence in the classroom, she would have reported being hit. Uninvestigated allegations may not be the best data on which to draw conclusions. The passage of time can change recollections, and sometimes, student complaints are ways of shifting responsibility for a problem from the student to the teacher. (To be fair, though, sexual complaints don't usually come from the latter cause. But memory can play tricks on all of us.)
But in any case, it sounds as if you're distrusting all teachers because a small minority may have behaved inappropriately. It's possible to indict parents in the same way. For instance, the National Children's Alliance reports that over half a million children are the victims of abuse--and 77% of those are abused by parents or guardians.
https://www.nationalchildrensalliance.org/media-room/national-statistics-on-child-abuse/That's a horrible statistic. But it shouldn't cause us to lose sight of the fact that most parents are not abusers, any more than most teachers are sexually inappropriate in the classroom.
As far as political lean is concerned, here's what the Heritage Foundation (a conservative organization) had to say:
A nationally representative survey of K?12 teachers does not support the idea that America?s public school teachers are radical activists, although conservative and moderate parents may find it disconcerting that nearly six of 10 teachers believe that white supremacy is a major problem in the United States. The survey results indicate that, while teachers tend to be somewhat left of center on many topics, their responses were not particularly close to positions held by the average liberal. Overall, the results could be welcome news for parents who are concerned about the growing influence of progressive ideology in public schools.
In looking at teacher influence on curriculum, it's important to remember that curriculum in K-12 schools is not controlled separately by each individual teacher. Rather, curricular decisions are made by grade level and/or department and are usually approved by local school boards. In fact, major decisions are normally controlled by national and state standards, as well as local school board policies. Teachers may have considerable autonomy in how they implement the curriculum, but usually not in terms of what the curriculum is or what texts and other instructional materials are used to support it. So when I talk about educators making choices, I'm talking about group decisions made based on consistent guidelines.
In contrast, censorship attempts are very often made by small groups of parents whose opinions may or may not be representative of the parents as a whole. It's one thing for parents to advocate for alternative instructional materials for their students. But all too often, the thrust is making those choices for all students. And even if one accepts the premise that liberal indoctrination is happening now, the censors seem to want instead conservative indoctrination. Ideally, what schools should be doing is developing student intellectual abilities so that they will be able to make their own decisions when they reach adulthood. Teachers should give students the tools to evaluate different perspectives without being an advocate for any of them. (My students were sometimes frustrated because they couldn't get information like my party affiliation out of me. And when I had to play devil's advocate to balance a discussion, I made what I was doing clear.) If instead are preparing students to be decision makers, parents want hardcore indoctrination 24/7, they are welcome to home-school their kids.
On a final note, we should probably make some differentiation between really young students and teenagers. the former are more impressionable. The latter are usually pretty set in their ways. I counted myself lucky if I could get them to do their homework. The idea that I could change their politics, their religion, their sexual preference or their gender identity would be laughable in most cases.