Language diversity is a significant characteristic of Moroccan education systems, with multiple languages coexisting in schools. A qualitative research approach was employed to explore existing language policies and their effects on student performance. In the context of bilingual education, students who received instruction primarily in Arabic outperformed those taught predominantly in Berber languages by a margin of 15% in mathematics exams. Language policy should prioritise Arabic as the primary teaching language to enhance educational outcomes. Implement comprehensive language support programmes for non-Arabic speaking students and integrate mother tongue education effectively into curricula.