Through a focus on liberal academic and policy networks, this article considers how ideas and practices central to an educational "war on poverty" grew through connections between postwar Puerto Rico, Latin America, and New York. In particular, it analyzes how social scientific ideas about education's role in economic development found ample ground in the colonial Commonwealth of Puerto Rico as the island assumed the role of "laboratory" of democracy and development after the Second World War. The narrative then considers how this Cold War programming came to influence education initiatives in both U.S. foreign aid programs in Latin America and New York City in the 1950s and 1960s, particularly as the number of Puerto Rican students grew amid the Puerto Rican Great Migration. Ultimately, the article suggests a broader hemispheric and imperial framework in narrating the evolution of postwar education policy in the nation's largest city.