For AP Physics or Chemistry, how do we explain the origin of magnetism, and diamagnetism? Saying that "Well, it's a quantum mechanical effect" or "it is a relativistic effect" isn't much help in explaining it's origin. Are there semi-classical explanations or analogies, that high school seniors could grasp? Many responses I have received stated that the actual origin is so deeply rooted in QM and relativity that there are no useful analogies that can be made to high school students, as all analogies are highly misleading. Is that really so, or were these responses a bit cranky? Can you suggest diagrams that clearly show the difference between: ferromagnetism, antiferromagnetism, and ferrimagnetism?