This paper treats the assessment of knowledge as a component in the functioning of the learning institution as well as in the education system as a whole. It attempts to interpret the effects that the examination and assessment of knowledge have on the pupil. These effects are not always unequivocal or positive. The key question posed addresses motivation for learning, specifically the notion of grades as a motivation for learning. In seeking systemic answers, the paper begins with the viewpoint that one cannot expect all pupils to have an internal interest in all school subjects; nevertheless, they still have to study them. As a consequence, various questions arise, especially in regard to the assertion that, in dealing with learning motivation, internal motivation should be preferred over external motivation. In this interpretation, grades should not be viewed solely as external motivation. Grades can, indeed, act as internal motivation for learning and acquiring knowledge. It is necessary to strive for the retributory principle of fairness in assessment and in regard to assessment criteria, while emphasizing that the teacher should be aware of the various circumstances that influence motivation for learning, the learning process itself, and the child's demonstrated level of knowledge. But such circumstances, it is asserted, should not be included among the criteria used in assessing the pupil. The teacher can use other motivational factors in the classroom to help give the pupil a positive motivation to learn. (Contains 14 references.) (Author/SLD)