Abstract The year 1917 marked a critical moment in the relationship between the United States and its Puerto Rican colony. It was the year the U.S. Congress approved the Jones Act, which further consolidated the island’s colonial relationship to the empire. Through the Jones Act, U.S. Congressmen granted Puerto Ricans U.S. citizenship. In turn, Puerto Rican men were asked to fulfill the obligations of their new colonial citizenship and join the U.S. military. The Porto Rican Regiment provided 18,000 colonial military recruits to guard the Panama Canal during the war. How did historical actors make sense of this new colonial citizenship? How did they interpret, debate, and adapt to the newly consolidated colonial status? This essay examines how local teachers and educators defined colonial citizenship. Puerto Rican teachers struggled to promote a citizenship-building project that cultivated student commitment to the patria (the island), while acknowledging the colonial relationship to the United States. In the late 1910s and throughout the 1920s, teachers debated military participation in World War I and the rights and obligations of U.S. citizenship. At the core, these debates were informed by anxieties over broader changes in constructions of gender. In the 1920s, Puerto Rico women aggressively and persistently challenged traditional gender norms. Working-class women joined the labor force in ever larger numbers and led labor strikes. Bourgeois women became teachers, nurses, and social workers. Both groups were committed suffragists. The historiography on citizenship and gender in the 1920s has focused on women’s emerging role in public spaces and their demands for just labor rights and the franchise. In this article, I propose we look at teachers, as intermediate actors in the colonial hierarchy, and examine their anxieties over changing gender norms. They debated men’s capacity to serve in the U.S. military and promoted modern physical education for the regeneration of boys and girls in the service of their patria. Debates among teachers in the 1920s sought to define the new category of colonial citizenship. As they did so, they helped liberalize some gender norms, while ultimately reinforcing patriarchy.