A wave function of quantum mechanics is regarded as a vector potential having a component only in a .theta.-direction of polar coordinates (r, .theta., .phi.). The result of applying a rotational vector operation to the vector potential is regarded as a magnetic field. The result of applying the rotational vector operation to the magnetic field is regarded as an electric field. A drawing on a plane or a three-dimensional model is configured to express both the magnetic and electric fields or one of the fields. The drawing or the model, as an educational tool, visualizes the figure of an atom, enables educands to have a close feeling toward sciences, and especially quantum mechanics, and enables them to have concrete images of various physical phenomena in the atom. The present invention, therefore, provides an educational tool that prevents educands from going away from sciences due to lack of an adequate educational tool of sciences and raises their interest in quantum mechanics inclined to be biased only toward mathematical research.