RESUMO
Background: Currently global competitiveness is the main thrust of the country's education department, raising the quality of education in the Philippines has become a priority for government officials, who see it as one way to address other teaching and learning challenges. Hence, this quasi-experimental research aimed to determine the influence of lingua franca-based and English-based instruction on the science performance of Grade ten students. Methods: The respondents of this study were forty-six Grade ten students out of the total population of fifty-three. Out of the forty-six respondents, twenty-three students were assigned to the experimental group and were taught using lingua franca-based instruction, and the remaining twenty-three were taught using English-based instruction. A researcher-made test was prepared and underwent validity and reliability tests. Mean was used to determine the science performance of the students, t-Test was used to test the significant difference between the students' science performance before and after teaching using lingua franca-based instruction and English-based instruction, and Cohen's d was used to compare two means in determining the effect size. Results: It was found that both groups exhibited fairly satisfactory science performance in the pre-test, and in the post-test, the control group reveals satisfactory Science performance while the experimental group shows very satisfactory science performance. No significant difference was determined between the pre-tests of both groups and significant differences were determined between the pre-test and post-test of both groups, and in the post-test of both groups, a large size effect was obtained in using the lingua franca-based medium of instruction on the science performance of the students. Conclusions: Hence, the practice of Lingua Franca-based instruction exhibits positive and desirable results in improving the performance of the students.
