In this paper I examine Peirce's epistemological and ontological theories and indicate their relevance to educational practice. I argue that Peirce's conception of Firsts, Seconds and Thirds entails a fundamental ontological realism. I further argue that Peirce does have a theory of truth, that it is a particular non-traditional "correspondence" theory, consistent with, and implicit in, an over-arching position of pragmatic realism. Peirce's epistemological position is subject to misinterpretation when the ontological realism on which it rests is overlooked. Finally I suggest that such a re-consideration of Peirce's pragmatic ontology and epistemology in an educational context is needed.