Abstract: The paper reports findings of a study that sought to examine the effect of innovative teaching methods on students’ mathematics self-efficacy in three-dimensional geometry in public day secondary schools in Musanze District, Rwanda. The study was based on Self-Efficacy Theory and Social Cognitive Theory. A mixed-methods research design employing quasi-experimental and descriptive approaches was used for the study. Multistage sampling techniques were used to select a sample of 269 students from public day secondary schools in Musanze District. Students’ mathematics self-efficacy questionnaires, achievement tests, and semi-structured interview guides were used to collect data from respondents. Quantitative data were analyzed using descriptive statistics and an independent samples t-test, while qualitative data were analyzed thematically. The results indicate that students exposed to innovative teaching methods attained slightly higher mathematics self-efficacy scores than students taught using traditional instructional approaches. However, the difference was not statistically significant, indicating that innovative teaching methods did not significantly influence students’ mathematics self-efficacy beliefs in three-dimensional geometry. The study provides a basis upon which mathematics teachers, curriculum developers, and educational policymakers can strengthen learner-centered instructional approaches and create supportive learning environments that promote students’ confidence, motivation, and participation in mathematics learning.

Abstract: Persistent gender disparities in mathematics achievement, particularly in three-dimensional geometry, continue to raise concerns about the effectiveness of instructional approaches used in secondary schools. This study examined the differential effects of gender on students’ academic performance in three-dimensional geometry under innovative and traditional teaching methods in public day secondary schools in Musanze District, Rwanda. The study was guided by Constructivist Learning Theory and Cognitive Load Theory and employed a quasi-experimental research design. Multi-stage sampling techniques were used to select a sample of 269 students from public day secondary schools in Musanze District. Data were collected using Mathematics Achievement Tests and analyzed using descriptive statistics and Two-Way Analysis of Covariance (ANCOVA). The findings revealed that gender had no statistically significant effect on students’ academic performance in three-dimensional geometry after controlling for prior mathematical knowledge. The interaction effect between gender and instructional method was also not statistically significant, indicating that innovative teaching methods benefited both male and female students equally. However, students taught using innovative teaching methods achieved significantly higher academic performance than those taught using traditional instructional approaches. The findings provide empirical evidence that innovative teaching methods can improve students’ achievement while promoting gender equity in mathematics learning. The study therefore supports the adoption of learner-centered instructional approaches to enhance academic performance in three-dimensional geometry across secondary schools.