I actually refused to read Huck Finn when I was in school.
Due to the racism that I already faced at that school, I wasn't enthused to be hearing white classmates use that word and have it essentially sanctioned. I think I sat through one reading of it, and a kid said the n-word and everyone laughed and looked at me...and I said no thanks. I spoke to the teacher after and she gave me an alternative to read in the library, a book that was written by a Black female author that took place in the same setting.
The fact of the matter is public education doesn't focus on challenging biases and dismantling racism. A kid reading those two books (I have read to kill a mockingbird privately) is not going to change their mind because the overall system doesn't talk about Black plight unless it's Black History month and then it's either MLK or Rosa Parks. That's not enough.
I don't think the books to be banned, but I definitely think Black students like myself should be able to opt out of circumstances that put the focus of racism, that we already deal with on us. I already dealt with racism every day, I certainly didn't want to deal with it while in class. For the time period perhaps the books were progressive, but for me, I didn't care for the environment I was already in. And...no, I'm not, as a young teen going to argue or have a conversation with other kids that didn't care for me. I think I was one of 3 Black kids in that school, so you can imagine how I felt.
As for the parent's motivation, it may be slightly different than mine, but anyone who just saying "it's a classic". That didn't really help or change the racist attitudes I had to deal with after kids read it, mostly because the framework wasn't there.