The Effectiveness of Mother Tongue as a Medium of Instruction in the Learning Development of Grade 1 Pupils at Baybay Elementary School

Background and Aim: The language of education is essential for how well children learn. The K–12 reform in the Philippines made Mother Tongue-Based Multilingual Education (MTB-MLE) a part of Kindergarten through Grade 3 to help kids read, understand, and participate more in class. Although global research validates the advantages of mother tongue instruction, specific evidence from Philippine schools is still scarce. This study aimed to determine how well MTB-MLE helped Grade 1 pupils at Baybay Elementary School in Ozamiz City learn and grow. It wanted to find out what subjects were taught in Cebuano, how mother tongue instruction affected understanding, and how it affected student involvement in the classroom. Materials and Methods: A descriptive qualitative case study methodology was used. Data were gathered through semi-structured interviews with five Grade 1 kids, supported by teacher interviews, classroom observations, and document analysis. Triangulation was utilized to strengthen the credibility of the findings, and the data were assessed thematically. Results: The findings indicated that Cebuano was predominantly utilized in subjects such as Araling Panlipunan, Edukasyon sa Pagpapakatao, MAPEH, and Mother Tongue. It was also used as a support language in Mathematics and English. Students said they understood and remembered things better when taught in Cebuano. Classroom observations showed students were more active, confident, and excited during mother language instruction. Conclusion: The study concludes that MTB-MLE improves Grade 1 students' understanding, involvement, and sense of cultural identity. It shows that teaching in a person's native language is not only a good way to teach, but it also changes society by connecting school and community and supporting Sustainable Development Goal 4 (Quality Education).