I think what bothers a lot of readers is that the "age appropriateness" sounds like an after-the-fact justification for removing a book on religious grounds.
I think Shakespeare isn't age-appropriate for high schoolers. (ROMEO AND JULIET IS NOT A ROMANCE STORY, KIDS! PLEASE BELIEVE ME ON THIS.) You could argue that Huck Finn isn't really age appropriate either. Uncle Tom's Cabin may have important historical significance, but it's *not* a kid's book. And so on.
We don't teach books in high school because they are "age appropriate" -- if we did, half the curriculum would be VERY different. I'd day that 90% of high school literature was originally written towards an adult audience.
We teach those books because they raise (or raised) important issues and we want to teach those issues to our citizens. High school is pretty much the last chance to dispense mandatory knowledge in our country, so there you have it.
If the school board really went through and weeded out everything above The Babysitter's Club level, they might have... a consistent argument. A terrible one, but a CONSISTENT one. But saying
oh, see this book that offends Christy McChristerson? It's...ah...not age appropriate. Yeah, that's it. Also, it attracts rats. Buh-bye. <--- That? That is censorship. It's not a reasoned, "here's what our budget will allow" or "gee, no one checks it out anyway because it's at a reading level higher than the students, so why keep dusting it once a year" decision. It's a "our religion doesn't like this book" decision. And THAT bothers me.
