If you think you have to get an A in my classes to please me, you're in the wrong class. In college I struggled in a number of the classes I took, especially if they had anything to do with philosophy, math, or logic. I stunk at those subjects. But I tried as hard as I could. I am incredibly blessed to have finished my college degree. It's not like I studied or anything in high school. (You wouldn't have either if you grew up in Hawaii.) Deciding to become a real student (that is, someone who actually studies) was the first step toward me becoming a teacher. I had completely run out of excuses not to study.
So take courage students. "The glory of God," wrote Irenaeus (an early church father), "is man fully functioning." That's true whether you're a student trying your hardest to get a good grade on an exam or a prof just trying to finish his teaching career well.