When public education began in the United States, it wasn’t so much about educating kids as it was about sorting them.
The common belief of that time, and for years after, was that not every child could learn. Some were just born to be farmers or ditch-diggers, while others were natural doctors and lawyers. And so the point of public schools was just to sort kids into groups so we could decide where to send them (college or back to the farm). An A-F letter grade system and a bell curve worked well for this. That was the theory, anyway.
Fast-forward 150 years, and we know that every child can learn. We don’t want to sort them; rather, we want every child to reach their potential. And if that’s the goal, it’s not particularly helpful to assign an arbitrary number of points and a single letter grade that incorporates knowledge, skills, attendance, behavior, participation, attitude…and anything else we want to throw in there. That’s why schools are now moving towards proficiency based scoring and reporting (sometimes called competency-based, standards-based, or mastery learning).
Proficiency/Mastery based scoring and reporting keeps the focus where it belongs: student learning.