While the number of impact evaluations has increased in international development, the use of evidence has remained an issue. This study investigates and conceptualizes how a development agency can use evidence to improve and expand its development programs, taking the case of the Indian NGO "Pratham." In a series of experiments with researchers, Pratham developed and refined their learning agenda to search for a better strategy to improve children's foundational learning. Pratham has also regularly conducted a nationwide survey on children's foundational learning. Data from the nationwide survey demonstrated the problem in children's foundational learning, and evidence from experiments showed an option for an effective strategy to address it. The search, learning, and communication cycle using data and evidence, conceptualized from the case of Pratham, would enhance the effectiveness of development agencies to better support educational development.