Language diversity is a significant characteristic of multilingual South Africa, where multiple official languages are recognised and used in educational settings. An action research study was conducted involving teachers, parents, and students to gather data through surveys and interviews. Focus groups were also used to explore perceptions and experiences related to language use in the classroom. The analysis indicates that a bilingual education model significantly improves student performance in mathematics and English compared to monolingual instruction. Specifically, 72% of students reported better understanding when taught in their first language before moving on to English. Language policy plays a critical role in educational success for multilingual South African students, particularly in secondary education settings. Adoption of the bilingual education model should be promoted as a best practice to enhance academic achievement and reduce linguistic barriers. language policy, multilingualism, education outcomes, Gauteng province