Abstract

This study investigated the effectiveness of TETRAS (Trip Exploration into Trigonometric Ratios: An Activity Sheet), integrated with the HiPER Scientific Calculator, as an instructional strategy for teaching trigonometric ratios to Grade 9 students. Anchored in Situated Learning Theory, the study addressed learners’ difficulty understanding complex trigonometric concepts through contextualized and technology-supported instruction. It aimed to support conceptual understanding, problem-solving skills, and engagement through authentic and interactive learning experiences. The study employed a quasi-experimental design and used cluster sampling to select participants from the Grade 9 population. Researcher-made instruments—including pretests, posttests, surveys, and observation checklists—were validated by experts and pilot-tested. Quantitative data were analyzed using descriptive and inferential statistics, particularly a paired t-test, to determine differences in performance. Students’ perceptions of authentic context, social interaction, and constructive learning were gathered through a Likert-scale survey. Participants had a balanced gender distribution, and most were aged 14–16 years. The intervention produced highly significant learning gains. Students also reported favorable perceptions of authentic-context application, constructive-learning support, and social interaction. Reported challenges included mobile-device notifications, difficulty with some lesson components, technical problems, and unequal access to devices. The findings indicate that TETRAS integrated with the HiPER Scientific Calculator supported students’ conceptual mastery and engagement in trigonometric ratios. The study recommends refining the worksheet design, simplifying instructions, adding gamified elements, and ensuring equitable access to technology. Overall, the findings support the use of authentic, technology-enhanced learning environments in mathematics education.