Teachers in Korea have recently confronted new challenges as the population of linguistically and culturally diverse students increases. Ethnically diverse students as well as Korea-born students returning from long residences in foreign countries have great difficulties orienting themselves within Korean schools due to lack of Korean language proficiency and cultural differences. We named this student group as Korean language learners (KLLs) and investigated teacher perspectives on effective mathematics pedagogy for KLLs. Using two educational models for English language learners (ELLs)—Cummins’ Quadrant Model and the Sheltered Instruction Observation Protocol (SIOP) Model—we examined survey results of a small group of elementary teachers in South Korea in terms of effectiveness and feasibility of the ELL models.