As transfers of educational ideas across countries accelerate in the twenty-first century with globalization, studies on educational change have lagged in foregrounding the importance of cross-national contexts when ideas traverse borders. This qualitative study investigates 30 Singapore teachers' perceptions of challenges involved in implementing differentiated instruction from the U.S., to sketch the contours around the intersection of educational transfer and change. Through analyzing classroom discussions and assignments of teachers enrolled in a Masters-level differentiated instruction course, we found that teachers' perceptions of implementation challenges clustered around technological, sociocultural, and political concerns. Challenges associated with differing technological conditions (e.g., class size/space and teacher capacity) and sociocultural norms (e.g., emphasis on control, results, and teacher-centered teaching) bring to fore how perceptions of origin and destination contexts shape reception of educational ideas, like differentiated instruction. Postmodern ambiguities around norms, objectivity, and evidence in a globally porous world further complicate teachers' concerns. In concluding, we propose a comparative educational change framework through which educational change and transfer can be viewed and argue for the need to scrutinize the influence of cross-national contexts when studying educational change across borders.