I wondered the same thing with my DS7. I was told that no matter how far ahead they are accelerated in a subject the grading would not be modified. I had sujected weighted grades like high school AP classes. If you get a 'B' then it's marked as an 'A' since the kid is really taking advanced subjects.

Maybe you could explain why you want the grades modified and quote programs like AP in high schools that take the modified grade approach.

Good Luck!