This study looks at Progressive-era conflict over education and educational policy in four states to answer questions about when, and how effectively, disadvantaged groups mobilize to influence the state. It draws on existing theories on social movements, the state, group conflict, and educational reform to develop new theories for explain the processes by which subordinate groups acquire concerns about education and the means to pressure the state to adopt their policy objectives. Critical attention is paid to formal organizations that mobilize individuals and present group demands and to the local and state structures that provide opportunities for influencing policy. The study is based on an historical analysis of four states, selected to vary on key attributes of race, ethnicity, and nativity as well as in organizational and state resources. %%% The research will advance our knowledge of how individuals, although disadvantaged because of their position in the community, may be able to have political influence when they become part of organizations. It moves beyond the usual perspective of educational sociology with an expanded theory on the role of organizations in providing resources, shaping demands, and expressing group interests. Through attention to historical detail, it will spell out the processes of change and illuminate the ways in which institutions are built.