Abstract
This study explored the effectiveness of micro-lectures in enhancing the academic performance of Grade 7 students in Science, specifically on the topic of Plant and Animal Cells. Rooted in cognitive load theory and Piaget's formal operational stage, micro-lectures are brief, focused instructional videos designed to improve content retention and engagement. A Single-Group Repeated Measures Design was used with 32 purposively selected students from a public secondary school in Sarangani Province, Philippines. Teacher-made assessments, validated through a Table of Specifications and inter-group reliability testing, were administered at five critical points: pre-test, three during-intervention tests, and a post-test. Results showed a significant increase in mean scores from 6.87 in the pre-test (Low proficiency) to 19.09, 16.81, and 19.37 in the during-intervention tests, and 17.37 in the post-test (Average proficiency). Notably, the number of students in the Low and Very Low categories dropped from 96.87% in the pre-test to 18.75% in the post-test. A Friedman Test revealed a statistically significant improvement in mastery levels following the intervention (χ² = 45.98, df = 4, p = 0.00). The study concluded that micro-lectures are an effective supplement to traditional instruction, fostering improved comprehension and retention among junior high school students. It is recommended that micro-lectures be expanded to other topics and paired with interactive strategies to maximize student engagement and learning outcomes. These findings contribute to the growing body of evidence supporting microlearning as a scalable, effective pedagogical tool in secondary education.