Abstract
While current research shows that civic education improves multiple political outcomes, its impact on ethnic tolerance remains unclear. Civic education may foster outgroup tolerance by teaching respect for diversity and promoting a shared national identity, but it may be counterproductive when emphasizing ethnic nationalism. I investigate this question by analyzing (1) a reform in Singapore that quasi-randomly assigned students to a new civic education course and (2) the International Civic and Citizenship Education Study (ICCS) data. Both studies reveal no improvement in ethnic tolerance from civic education. Given these findings, I explore whether the effectiveness of civic education depends on various contextual factors, including country-level differences (regime type, centralization, and indoctrination), classroom openness, and students' ethnic backgrounds. Only classroom openness appears to be an important moderator in amplifying civic education's impact on ethnic tolerance. These results highlight the pivotal role of pedagogy in shaping civic education's effects on ethnic tolerance.

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