My DS9 in 3rd grade is taking 3rd & 4th Grade math. We get our grades on their website as they are posted and then a report card each quarter. So far, we only have one grade for Math, which I think is for 3rd grade math work. I am getting graded papers at home for both. Right now I don't know what the grade is so far for 4th grade Math. I could just average his papers and figure it out.

How is it usually handled when a student does 2 grades at the same time?

I'm mostly concerned he feels challenged but I think it is nice to know where he stands with his grades.