This study aimed to assess the effect of language intervention activities on the performance of fourth-grade pupils at Divisoria Elementary School in Santiago City, Philippines for the School Year 2023-2024. The research involved 82 participants, with 41 learners assigned to the Control group and 41 learners to the Experimental group. A quasi-experimental design, specifically the pretest-posttest design, was employed to measure the effect of the intervention. Data analysis was conducted using Microsoft Excel, ensuring fair treatment of participants' responses for frequency calculation. A paired sample t-test was utilized to analyze significant differences between the two groups pre- and post-testing, with statistical analysis performed using the Statistical Package for Social Sciences (SPSS) version 20 software. The findings revealed a positive effect of language intervention activities on language performance. The experimental group exhibited a significant improvement in mean performance from the pre-test to the post-test, indicating a substantial increase in their language performance. In contrast, the Control group's mean performance showed minimal change, highlighting the importance of language intervention activities in enhancing language skills. The results underscore the significant improvement of language intervention activities on the identified least mastered competencies of Grade 4 students. A proposed strategic intervention material is the output of this study and it was recommended that the crafted material be adopted by elementary teachers in the school and other teachers in the school division as an additional learning material to address the weaknesses of the learners along the identified least learned competencies.
