It helps to understand some of the possible motivations and added a few more things to what I had found in looking myself.
That being said, the principal as far as I know has stated that the exclusionary status of valedictorian and class ranking is the driving factor for doing away with it, and in addition to those, other academic achievements are being shelved, there is a recognition for students at graduation that score at certain levels on the AP tests, and an award for students who qualify as having taken a more rigorous scholastic class schedule and another one that I can't remember exactly at the moment but has to do with cords at graduation that are all being cut out because they are stratifying awards that exclude a lot of the student body (class sizes are over 1K per grade) so while I can see some valid reasons, I am not exactly thrilled about a system that de-incentivizes scholastic achievement for the achievement oriented kids, which I think is an unintended consequence of a policy change like this.