American high schools are already doing a form of this, with certain classes earning more than a 4.0 score in GPA calculations. 5.0 is quite common now, with 6.

American high schools are already doing a form of this, with certain classes earning more than a 4.0 score in GPA calculations. 5.0 is quite common now, with 6.0 and even 7.0 scores on individual classes being possible.