This article discusses the study of educational theories and ideas. Based on analyses of primarily the Danish scene, positing similarities with the other Nordic countries, we identify and investigate three main and today dominating approaches: a philosophical approach focusing on the content of the ‘great’ thinkers’ ideas, their logical-coherence and/or moral-ethical value; a historical approach centering on individuals and their educational ideas expressed as views in a realistic and contextual story; and a Foucauldian approach which analyzes educational ideas and theories through their place in power-knowledge constellations. On the backcloth of analyses of the ontology and epistemology operating in these approaches we conclude that they all ignore the systematic study of the social context in which ideas and theories are conceived and we argue for a social space and social history approach as a way to fill out this epistemological vacuum.