“Students were not collaborating with each other the way that we would like them to. Their choice of courses was being guided by their GPA and not their future education plans.”

Valedictorian is selected by multiplying your GPA times the value of the class. AP classes are worth 5 points and Shop classes might be worth 3 points. For example students who wish to go on to engineering are discouraged from taking shop classes because it would lower their chances of being valedictorian. It goes the same with art and music classes. They will hurt your score although may benefit you in many ways. It's a very complicated subject that is glossed over by the the author just to enflame some people.