DD7's teacher told us when we went over her report card that she has to mark things in a way that allows room to show future progress.

She also said that when they do science projects, that the kids never get a 4 (independent work) because they always have to help the kids so that supplies don't get broken. So the best they can do is get a 3, (at grade level).

I think you are right when you say that the teacher has to "ding your ds" for something!