The Effectiveness of the Discovery Learning with an Ethnomathematics Focus on Ratu Boko Temple on Students’ Learning Achievement and Self-Efficacy

The purpose of this study was to examine the effect of a discovery learning approach with an ethnomathematics focus on students’ learning achievement and self-efficacy. This study was conducted during the 2024–2025 school year with eighth-grade students at a junior high school in Yogyakarta, focusing on the topic of plane figures. There were 30 students participating in the study. A pre-experimental strategy with a one-group pretest-posttest design was employed. The sample consisted of a single class that implemented the ethnomathematics-infused discovery learning approach. Data were collected through learning achievement tests, self-efficacy questionnaires, and observation sheets. The results showed a significant increase in the mean learning achievement score from 37.50 to 82.00, while students’ self-efficacy increased from 61.53 to 73.40. Inferential analysis using the t-test showed a t-value for learning achievement of t = -22.35 < -1.699 with a p-value < 0.001, while self-efficacy had a t-value of t = -9.310 < -1.699 and a p-value < 0.001. These findings indicate that the discovery learning approach with an ethnomathematics focus is effective in improving students’ learning achievement and self-efficacy.