The year 2016 marks the 100th anniversary of the American Educational Research Association and the 50th anniversary of the publication of "Equality of Educational Opportunity," known as the "Coleman Report." These key moments in the field's history ushered in important paradigm shifts in the practice of education research; in how the relationships among poverty, inequality, and schooling were understood; and in the research-policy nexus. This conceptual synthesis of the history of education research in the United States is focused on poverty knowledge in both periods. The authors trace the rise of education as a field of study, the place of poverty in the emergent science of education, and the extent to which leading researchers have acknowledged, analyzed, or contested poverty. The "Coleman Report" advanced a new paradigm for analysis while being firmly rooted in earlier traditions. Coleman's analytical approach has become common sense in educational policymaking in the form of the accountability movement. The report's fundamental insights about the relationship between poverty and student achievement too often remain unacknowledged by U.S. policymakers.