Is this a polite way to ask her to help me increase my grade? If not, what else should I add?

Dear Mrs. Mcginn,
I checked my math grade and discovered that it was 86. From here to the end of the semester, is there any chance I can get it to 90? If not, can I receive extra credit or redo the assignments that are causing my grades to drop?

Sincerely,
Katrina Karaninsky