Although most teacher education programs include instruction in the basic science of psychology, practicing teachers report that this preparation has low utility. Researchers have considered what sort of information from psychology about children's thinking, emotion, and motivation would be useful for teachers' practice. Here, I take a different tack. I begin by considering three varieties of statements in basic science: empirical observations, theoretical statements, and epistemic assumptions. I suggest that the first of these can support classroom application, but the latter two cannot. I use that conclusion as a starting point for considering the instruction of prospective teachers in psychology.