Is there a way to know how many repetitions one needs for learning?

This may seem to variable to even ask this question. Here's what I'm thinking. I have a feeling somebody has some insight to this.

My DS9 knows his spelling words on the second day. Maybe the majority of the class needs more days, I'm not really sure. It seems like if the student consistently only needs 2 repetitions, then they could go onto something else at that point.

This is a very easy example but I'm wondering about applying to other areas. Would there be a way of saying for a fact he only needs 2 repetitions of his social studies, for example ,so he could go onto something more meaningful during his school day? Is there a way to know how many repetions some one needs for learning? It seems like a lot of the learning is just retaining the information, learn the steps, not so much problem solving and reasoning.