Development of Simredity: An Interactive Strategic Intervention Material in Teaching Non-Mendelian Genetics to Grade 9 Learners

Abstract

Genetics, particularly Non-Mendelian Patterns of Inheritance, remains one of the most difficult topics for secondary learners due to its abstract nature and the higher-order reasoning it requires. This challenge is more evident in rural Philippine schools where access to interactive learning resources is limited. This study developed and evaluated SIMredity, an Interactive Strategic Intervention Material designed to enhance Grade 9 learners’ conceptual understanding of non-Mendelian inheritance through print-based, visually enriched, and story-integrated activities. Guided by the 4D Model (Define, Design, Develop, Disseminate) and grounded in Constructivist Theory, Cognitive Load Theory, and Self-Directed Learning Theory, the study employed a mixed-methods design incorporating needs assessment, expert evaluation, quantitative testing, and qualitative feedback. Results from the needs assessment with six Science 9 teachers identified persistent learning difficulties in incomplete dominance, codominance, multiple alleles, and sex-linked traits, along with a lack of engaging instructional materials. SIMredity was subjected to expert evaluation using the Department of Education’s LRMDS evaluation tool for print resources and received a Very Satisfactory rating across all components, with a 72.2% percentage agreement among evaluators, confirming its quality, clarity, and content accuracy. Implementation with 35 Grade 9 learners further demonstrated its effectiveness, as shown by a significant increase in mean scores from 9 in the pre-test to 21 in the post-test (t = –22.21, p < 0.001). Learners described the material as colorful, interactive, easy to follow, and helpful in supporting independent and self-paced learning. Overall, the findings indicate that SIMredity is a valid, usable, and effective instructional tool for improving learners’ comprehension of non-Mendelian genetics, especially in resource-constrained educational settings.