"suggested for sixth-, seventh- and eighth-graders by the Columbia University Teachers College's Reading and Writing Project"
Hmmm, so the "experts" recommended these books. Why am I not surprised?
It might be that the teachers saw a list of recommended books and purchased a bunch of them. Many classroom libraries have several hundred (I am approximating) books. I wouldn't think teachers would feel the need to read them all, especially if they felt they could trust the list.