Abstract
BACKGROUND: GeoGebra® (a registered trademark of the International GeoGebra Institute) is dynamic, user-friendly, and open-source software that effectively connects geometry and algebra. By reducing abstraction and procedural demands, it facilitates students' conceptual understanding. This study investigated the impact of GeoGebra integrated mathematics instruction on Grade 9 students' achievement, conceptual understanding, and motivation regarding quadratic functions. METHODS: A quasi-experimental design with non-equivalent control groups was employed, involving 42 students in the experimental group and 45 in the control group, drawn from different intact classrooms in Worabe Town Administration, Ethiopia. The experimental group received instruction using GeoGebra, while the control group followed traditional teaching methods. The intervention was grounded in social constructivist theory. Data collection instruments included pre- and post-tests for mathematical achievement and conceptual understanding, as well as a motivation questionnaire. Statistical analysis was conducted using SPSS. RESULTS: The experimental group showed statistically significant improvement in both conceptual understanding and problem-solving performance compared to the control group (p < 0.05). Additionally, students in the GeoGebra-integrated instruction group reported significantly higher levels of motivation toward learning quadratic functions. CONCLUSIONS: GeoGebra-integrated instruction has the potential to improve student achievement, reduce time spent on routine calculations, and address challenges related to multiple representations in mathematics. Furthermore, it enhances student motivation and engagement with critical mathematical concepts. These findings support the inclusion of dynamic mathematical software like GeoGebra in secondary mathematics instruction, especially for topics requiring visualization and symbolic reasoning.