Magister Artium - MA / This study is an investigation of the application of dual-medium and parallel-medium models of bilingual schooling as implemented at two historically disadvantaged primary schools in the Western Cape. The author assumes that parallel-medium in practice uses only one language of learning and teaching (LoLT), and thus lead to monolingual classroom practice. The author used qualitative techniques (observations, interviews, and document analyses.), and triangulation method, to understand the application of dual-medium and parallel-medium instruction and the support of principals and teachers in their understanding of the design models. Observations were made in Grade 7 classrooms at selected and document analyses, triangulated with interviews conducted with principals and teachers to expound the effective practice of bilingual education at school and classroom level. Document analyses were made of classroom materials (various literary artefacts) used for the development of language proficiency. in addition, how it contributes to the Grade 7 learners academic perform and language development in dual-medium and parallel-medium classrooms. / South Africa