A model based on the theory that classroom interaction and the political content of class discussion are the means to achieving a sense of political efficancy is tested on Canadian elementary students. Classroom participation, classroom politicization, sense of school efficacy, political knowledge, various personal characteristics, as well as sense of political efficacy are measured to ascertain their relative influences on the last variable. The results show class participation having no reliable affect. Personal characteristics, especially grade level, and classroom politicization do influence a student's accumulation of political knowledge. Grade level has an independent affect on school efficacy as, to a lesser degree, does political knowledge. The culminating influence of school efficacy out-weighs that of political knowledge in shaping a student's sense of political efficacy, and though the two appear as the most important variables, the greater influence of school efficacy overwhelms the original hypotheses of the importance of classroom interaction. (JH)