International Journal of Geometry Research and Inventions in Education

Application of GeoGebra-Assisted Problem-Based Learning Model to Strengthen the Learning Interest of Eighth Grade Junior High School Students

Willy Ruben Sihombing — 2025-08-01

Learning interest is a psychological drive that allows students to learn something consciously, calmly, and with discipline. A lack of learning interest was observed in one school in West Jakarta. This is a significant issue as learning interest directly impacts the quality of education. Therefore, the purpose of this study is to investigate the application of a GeoGebra-assisted problem-based learning (PBL) model to enhance the learning interest of eighth-grade junior high school students. Additionally, the paper will discuss the application of this GeoGebra-assisted PBL model from a Christian perspective. This research utilizes a descriptive qualitative method, with data collected through observation sheets, lesson plans, and teacher reflection sheets. The analysis of the research data demonstrates the positive effect of the GeoGebra-assisted PBL model on learning interest. This is evidenced by observed changes in student behavior that align with the indicators of learning interest. Thus, it can be concluded that the application of the GeoGebra-assisted PBL model can foster and strengthen students' learning interest. The PBL model offers a platform for student exploration, with GeoGebra acting as a supportive tool. The diverse features of GeoGebra facilitate the learning process, thereby fostering a sense of enjoyment and interest. However, due to certain limitations in its application, educators must guide students in its use.

The Effect of Self-Explanation Learning Strategies on Students’ Understanding of Mathematical Concepts

Subhan Ajiz Awalludin — 2025-08-01

This study investigates whether a structured self‑explanation strategy improves secondary students’ conceptual understanding of geometric transformations. Employing a quasi‑experimental nonequivalent posttest‑only control group design, the research sampled two intact eleventh‑grade classes from a public high school. The experimental class received worksheet-embedded prompts guiding them through four phases of self-explanation, whereas the control class experienced conventional instruction. Assumption checks confirmed normality and homogeneity, and an independent‑samples t‑test compared posttest performance. Students taught with self-explanation achieved higher scores on a five-item open-ended assessment of conceptual understanding than their peers in the control condition. The between‑group difference was statistically significant and accompanied by a large effect size (ES ≈ 0.83), indicating meaningful practical gains. Qualitative interpretation of score patterns suggests that explanation prompts facilitated integration across symbolic, graphical, and spatial representations and reduced common misconceptions in transformation tasks. These results align with prior evidence that metacognitive scaffolds deepen conceptual learning and support transfer beyond taught procedures. The findings imply that brief, structured self‑explanation can be feasibly integrated into routine lessons to enhance conceptual outcomes. Future research should explore retention over time, effects across diverse topics, and the comparative benefits of alternative metacognitive supports.

Solving Geometric Problems from the Perspective of Left and Right Brain Dominance

Syafruddin Kaliky — 2025-08-01

Problem-solving is an effort to find a way out of a difficulty so as to obtain a solution. Each child's problem-solving is different. This is influenced by the dominance of the brain in solving a problem. The purpose of this study is to describe the geometry problem-solving abilities of junior high school students in terms of left and right brain dominance. The research method is descriptive with a qualitative approach. The instruments used are test questions, questionnaires, and interview guidelines. The results show that students with left and right brain dominance types in solving geometry problems can fulfill all stages according to Gagne, which include Presentation of the problem, stating the problem in operational form, compiling work procedures, making hypotheses, and reviewing. The findings of students with left brain dominance in solving problems appear to be calmer and more patient, prefer to solve problems with formulas given by a teacher, need scratch paper in solving problems, tend to think with the chin supported by the right hand, and have neat writing. Meanwhile, students with right brain dominance in solving problems appear to move more, tend to have many ways, sometimes use their own way, work while speaking, and if they have scribbles, it will be very difficult to understand, and draw on blank paper with unclear images.

Mathematical Critical Thinking Skills: Students' Analytical Ability on the Topic of Circles

Saddam Al Aziz — 2025-08-01

Critical thinking skills are one of the important competencies of the 21st century that need to be developed through mathematics learning, especially in flat geometry, namely circles. One important indicator of critical thinking is analytical skills, namely the ability to analyze information, identify relationships between concepts, and draw rational conclusions. This study aims to describe students' mathematical critical thinking skills in the indicator of analysis in circles. The research used a descriptive quantitative approach with a sample of 31 eighth-grade students at a public junior high school in Padang City. The instrument consisted of one essay question that asked students to analyze two different arguments related to the concepts of diameter and chord, choose the correct argument, and provide logical reasons based on the concept of circles. Scoring was done using an analytical rubric with a score range of 0–5. The results showed that only 3.22% of students were able to analyze correctly with logical reasoning, 6.45% of students could choose the correct argument but without a conceptual explanation, 80.65% of students were unable to analyze correctly and tended to copy the arguments in the questions, and 9.68% of students did not provide answers. These findings indicate that students' mathematical critical thinking skills, particularly their ability to analyze circle-related material, are still low. This study emphasizes the importance of mastering basic concepts as a foundation for promoting critical analysis skills in mathematical problem solving.

Integrating Congruence Geometry in Strengthening Numeracy Among Junior High School Students: A Case Study

Elis Nurhayati — 2025-08-01

This study examined the effectiveness of integrating congruence geometry into contextual numeracy learning to enhance junior high school students’ mathematical reasoning. A qualitative case study with quantitative support was conducted with 32 eighth-grade students and one mathematics teacher at a public school in West Java, Indonesia. The intervention included eight lessons embedding geometric transformations—reflection, rotation, and translation—into culturally relevant numeracy tasks such as batik and tiling designs. Data were collected through pretests, posttests, classroom observations, and interviews. Results showed a 43% improvement in contextual numeracy indicators and a significant increase in students’ ability to recognize congruent shapes, explain geometric reasoning, and apply transformations to real-life problems (t(31) = 6.42, p < 0.001). Observational and interview data revealed greater engagement, collaboration, and reduced mathematics anxiety. Findings support the four-dimensional numeracy framework (Goos et al., 2014) and Battista’s theory of geometric reasoning (2007), emphasizing that contextual and culturally grounded tasks foster conceptual understanding and motivation. The study concludes that contextualized geometry-based numeracy instruction effectively promotes students’ understanding, transfer of learning, and confidence, offering implications for developing culturally responsive mathematics curricula.