We are defined, not by the labels others put on us, but on the labels we accept for ourselves. Therefore, choose to accept the labels that allow you to grow and prosper, and reject those that hold you back. So, given a choice between "Did poorly on test" and "Does well in class", which is the better label? Which fits better with other labels such as, "Writes effectively", "Works well with others" and "Makes people smile"? The choice is obvious: You know what you can do, and no one can take that away from you.