Enhancing Students’ Understanding of Functions and Graphs through GeoGebra-Based Instruction

Abstract

Proficiency in functions and graphs is fundamental in Senior High School mathematics, serving as a prerequisite for advanced courses in calculus, statistics, and real-world applications. This study employed a quasi-experimental two-group pretest–posttest design to compare the effectiveness of the Traditional Lecture Method (TLM) and GeoGebra-based instruction in teaching functions and graphs to Grade 11 GAS students at Dapa National High School, S.Y. 2022–2023. Fifty students were purposively selected and randomly assigned into two groups of 25 each. The TLM group was taught through lecture-discussion and chalkboard demonstrations, while the GeoGebra group used interactive software for dynamic visualization. Results showed that in the first trial run, the TLM group improved from 28.18% (Low Mastery) to 39.45% (Average Mastery), while the GeoGebra group increased from 30.27% (Low Mastery) to 68.71% (Moving Towards Mastery). In the second trial run, the TLM group advanced from 33.45% to 66.13%, whereas the GeoGebra group progressed from 35.76% to 80.21%. ANCOVA confirmed a statistically significant difference favoring GeoGebra (p < 0.05). Perception results revealed a grand mean of 3.17 (Moderately Perceived), with students strongly agreeing on GeoGebra’s user-friendliness, motivational value, and effectiveness in visualizing graphs. Findings suggest that integrating GeoGebra enhances mastery, motivation, and engagement, making it a valuable instructional tool for strengthening mathematics learning.