This paper argues that in teaching educational psychology, different experts often compartmentalize theories in substantially different ways, and there is considerable disagreement within the field regarding the dividing lines that separate various "isms." The four main "isms" (behaviorism, information processing theory, constructivism, and social cognitive theory) each provide unique insights about learning and instruction. The paper proposes an alternative approach to teaching educational psychology that focuses on the big ideas that are common to, or combine elements of, multiple "isms." Ten examples of such big ideas are explicated. The paper argues that such an approach has several advantages over the more traditional approach of identifying concepts, principles, and educational applications as lying within the domain of particular "isms." (Contains 57 references.) (Author/SM)