In order to help students achieve the goal of conceptual understanding teachers must not only know and appreciate the nature and value of such understanding but must know how concepts are learned. One point on which many studies of concept development to date seem to agree is that one person cannot give concepts to another at any level higher than that of simple recognition. Teachers can identify a concept for students and expect them to know it on the cognitive level of recall. But teachers cannot expect students to internalize it, to understand all its various interrelated facets and ramifications simply because they have labelled it. Concept learning is different from mere fact learning. A child may report facts accurately after reading a textbook and yet have no grasp of the concepts implied.