When I create a pledge, I am able to assign it to a class. When I add a discount to that pledge, how can I assign a class to it so it appears on reports?

I have our discounts going to account 5693. When I create a pledge, I assign it to class 710. Is there a way I can run a report on activity for account 5693 and show what of that is tied to my 710 pledges? In other words, when I run an activity report for class 710, why are my discounts in 5693 not showing up?