UNMASKING LEARNING DIFFICULTIES IN SENIOR HIGH CHEMISTRY: MASTERY LEVELS, LEAST MASTERED COMPETENCIES, AND GENDER ANALYSIS

Chemistry education continues to confront persistent challenges due to the abstract and multi-level nature of its representations, encompassing macroscopic, sub-microscopic, and symbolic dimensions, which frequently result in conceptual “black holes” among learners. This study investigated the overall mastery levels and specific learning gaps in Chemistry among Grade 12 STEM students at Mindanao State University – Sulu during the 2025–2026 academic year. Employing a descriptive-diagnostic research design, data were collected from 137 purposively sampled participants using a validated 50-item multiple-choice assessment. Findings indicated an overall proficiency classified as “Nearly Mastered” (Mean = 30.0), highlighting enduring deficiencies in full conceptual attainment. Competency mapping revealed relatively higher performance in observable topics, such as “States of Matter” (Mean = 0.74), contrasted with pronounced difficulties in structural and abstract domains, with “Molecular Geometry” identified as the least mastered competency (Mean = 0.11), underscoring the persistent challenge of three-dimensional visualization. Additionally, the Mann-Whitney U Test (p = 0.217) demonstrated no statistically significant gender differences, suggesting that conceptual barriers are uniformly experienced across the cohort. These results emphasize the critical need for pedagogical innovations, particularly the integration of technology-mediated instructional resources such as Electronic Strategic Intervention Materials (E-SIM), to effectively mediate the transition from observable phenomena to sub-microscopic comprehension within the BARMM educational context.