Let's all remember some of the ludicrous motions to ban popular books for kids based on the oddest reasons from school groups before. That's why I don't like the idea of this.
On one hand someone may say it's a good thing to restrict kids from "harmful books" - but what is harmful? It's too subjective. The top 11 books american groups tried to ban last year is an example of this -
most of these books aren't harmful for children unless a person has an odd viewpoint or is missing the point of the books entirely.
I was an advanced reader and my parents let me read adult fiction in middle school. Not every parent would agree with that - I met someone whose parents wouldn't let her read Judy Blume at any age. Having the parents decide for their children, and the children decide for themselves, versus a 5 person committee is what should take place.