Catcher in the Rye dropped from US school curriculum
It was just too remote from the lives of my students. Let's face it, Holden Caulfield had nothing in common with kids from the steel-manufacturing valley of Cleveland. They were more likely to want to punch the privileged, whiny sissy than relate to him. By the time I was teaching in private schools, Salinger's novel was too historically distant to be of any interest to my students.
On the other hand, Harper Lee's classic will be missed, as it spoke to a much broader range of adolescent experience.
[To be fair, Salinger's short story, "The Laughing Man", I think to be one of the great works in that genre of American fiction.]