Why the Grading System doesn't work

In Core, the average of all your percentages is taken and divided into two classes equally. You will either get an AA, a BB, a CC, or a DD. Or perhaps a Fail/Fail. However, as this class counts for TWO grades, and not one, the grading needs to be done differently. Take these two case studies:

Student A gets: 92%, 92%, 90%, 88%, 85%, and 81%. This is an (A/A/A/B/B/B) and averages out to be a 88%, which in Core would become a BB.

Student B gets: 87%, 85%, 85%, 81%, 80%, and 74%. This is a (B/B/B/B/B/C), and averages out to be a 82%, which in Core would become a BB.

Although these two students are obviously different, Student A undeniably better than Student B, they get the same grade. In the new system, Student A should get an A/B, and Student B should get a B/B.

Because Core is two classes on the report card, and not one, the grading scale should thus be different. Obviously, colleges look at GPA when accepting students and the aforementioned current grading scale is not conducive to helping students aspire to college. The new proposed system is:

90% and above: A/A
85-89%: A/B
80-84%: B/B
75-79%: B/C
70-74%: C/C
65-69%: C/D
60-64%: D/D
Below 60%: Fail/Fail

The reason for this is because, presumably, students who get in the high 80s have achieved a few A's and a few B's, and the grade should reflect that. Rather than give the student both B's, which presumes that they only maintained B's in their Core classes, the student should get an A and a B, showing that the student performed well in a few classes. This grading scale makes more sense and will better reflect students grades to be what they actually did in their classes.