Abstract. Understanding the psychological variables of learning mathematics at the high school level is important to designing effective teaching strategies that improve their active engagement and academic achievement in mathematics. This study validated the assumptions of the Self-Determination Theory and Social Cognitive Theory in the context of mathematics classroom learning. This research aims to fill the gap in the literature by confirming a structural equation model based on two combined theories, incorporating the latent variables of self-efficacy, persistence, interest, motivation to learn mathematics, and the perceived teaching quality, areas that have already been explored in previous studies. Data were gathered from 325 selected public high school students (junior and senior high school) using a multivariate-correlational research design. Results revealed that self-efficacy strongly influences motivation (β=0.823, p<0.001) and weakly influences persistence (β=0.267, p=0.003), while perceived teaching quality significantly impacts interest (β=0.769, p<0.001) and self-efficacy (β=0.328, p<0.001). Additionally, student interest enhanced self-efficacy moderately (β=0.471, p<0.001), further reinforcing its critical role in fostering confidence. Motivation to learn mathematics was found to be strongly associated with students' persistence (β=0.557, p<0.001). These findings led to developing a valid and reliable structural equation model characterized by strong psychometric properties and excellent model fit indices. The results profoundly emphasize the interplay of psychological and instructional factors in promoting engagement, motivation, and resilience among high school mathematics learners, offering valuable insights for enhancing teaching strategies and educational policies. High school students should cultivate self-efficacy and motivation in mathematics through self-reflection and goal-setting. Teachers are encouraged to adopt interactive, real-world strategies that enhance interest and confidence, while school leaders should focus on professional development to sustain student engagement. Future research can explore digital tools, gamification, and advanced statistical modeling to investigate non-cognitive factors shaping mathematics learning.

Keywords: Motivation; Perceived teaching quality in Mathematics; Persistence; Self-efficacy; Structural Equation Model; Student interest.