I want people to know the truth of the subject. If the subject is history, I think they should not only know the facts and the dates, but also the stories of the people involved along with their motives. If the subject is math, I don't just want a person know the answer to 9 X 9, but I want them to know how to get that answer. But here is the thing, if you know the truth of the subject, then you should be able to get good grades, though it is not a guarantee. Good grades are to be the fruit of learning the truth. People who focus on the grades may forget the truth, because they are trying to memorize answers and not go through the process of learning the truth.
By the way, there is a common parallel that I often hear. People want to go to heaven without getting to know Jesus. Biblically that's impossible. Jesus is the focus of heaven, but heaven is not the focus of Jesus. See, people want the reward of heaven, but they don't want to go through the process of getting to know and following Jesus.
Focus on the truth and the reward will come. However, if you focus on the reward, you may miss the truth.