Jurnal Math-UMB.EDU

VALIDITY AND PRACTICALITY OF ENGINEERING DESIGN THINKING-BASED STUDENT WORKSHEETS

Sukma Lestari, Masri, Risnanosanti — Sun, 01 Mar 2026 00:00:00 +0700

This study aims to determine the validity and practicality of Engineering Design Thinking (EDT)-based Student Worksheets (LKPD). The research employed a development research method using three of the four stages in the 4D (Four-D) development model, namely define, design, and develop. The research subjects consisted of one teacher and 29 students in the implementation class. The instruments used included expert validation sheets and practicality questionnaires. The results showed that the validity score of the LKPD reached 88.61%, which falls into the "very valid" category. The practicality score based on the teacher's assessment averaged 87.5%, while the students assessment averaged 85.3%, indicating a high level of practicality. Therefore, it can be concluded that the developed Engineering Design Thinking-based LKPD meets the criteria of being valid and practical for use in the learning process.

Keywords: Student Worksheets (LKPD), Engineering Design Thinking (EDT), Validity, Practicality.

MATHEMATICAL PROBLEM-SOLVING SKILLS AND STUDENTS' LEARNING INDEPENDENCE THROUGH PMRI BASED ON ENGINEERING DESIGN THINKING

Leni Pitriyani, Risnanosanti, Ristontowi, Rahmat Jumri, Adi Asmara — Sun, 01 Mar 2026 00:00:00 +0700

This study aims to observe the differences in students' mathematical problem-solving abilities and learning independence in learning with the Indonesian Realistic Mathematics Education (PMRI) approach based on Engineering Design Thinking (EDT), the Indonesian Realistic Mathematics Education (PMRI) approach, and conventional learning. This study is a quasi-experimental study with a pretest–posttest control group design. The study population was all seventh-grade students of SMP Negeri 7 Bengkulu City in the 2025/2026 academic year. Data analysis was carried out using one-way ANOVA. The results showed that there were significant differences in students' mathematical problem-solving abilities taught with the PMRI approach based on EDT, PMRI, and conventional learning (F = 3.629; p = 0.031 < 0.05). The average posttest of students' mathematical problem-solving abilities in the PMRI class based on Engineering Design Thinking was 28.75, the PMRI class was 26.84, and the conventional learning class was 24.42. In addition, there was a significant difference in student learning independence between the three learning groups (F = 3.734; p = 0.029 < 0.05). The average student learning independence in the EDT-based PMRI class was 73.94, higher than the PMRI class (68.95) and the conventional learning class (68.13). Based on these results, EDT-based PMRI learning is more effective in improving students' mathematical problem-solving abilities and learning independence.

Keywords: PMRI, Engineering Design Thinking (EDT), Mathematical Problem Solving Ability, Learning Independence.

DEVELOPMENT OF ESSAY INSTRUMENT TO MEASURE MATHEMATICAL CONCEPTUAL UNDERSTANDING ON SIMILARITY AND CONGRUENCE

Muhammad Faruq Wahyu Utomo, Novaliyosi, Aan Hendrayana, Fatah — Mon, 02 Mar 2026 00:00:00 +0700

This study aims to develop a valid and reliable essay test instrument to assess mathematical conceptual understanding in ninth-grade junior high school students, focusing on similarity and congruence. Employing a modified 4D model (Define, Design, Develop, Disseminate), the research involved designing a test blueprint based on seven conceptual understanding indicators, expert validation using the Content Validity Ratio (CVR), and field testing to evaluate construct validity, reliability, item difficulty, and discrimination indices. The results indicated that all test items were valid, achieved a high reliability coefficient (α = 0.83), and exhibited varied difficulty and discrimination levels meeting established criteria. Consequently, this instrument is capable of comprehensively measuring students' conceptual understanding and serves as an effective assessment tool in mathematics education.

Keywords: Essay Instrument, Mathematical Conceptual Understanding, Similarity and Congruence.

DEVELOPMENT OF PROBLEM-BASED LEARNING INSTRUCTIONAL VIDEOS ON UNIFORM AND UNIFORMLY ACCELERATED LINEAR MOTION FOR JUNIOR HIGH SCHOOL STUDENTS

Thu, 05 Mar 2026 00:00:00 +0700

Physics learning at the junior secondary school level on the topics of Uniform Linear Motion and Uniformly Accelerated Linear Motion often shows low conceptual understanding due to limited use of contextual and visual instructional media. This study aims to develop and examine the effectiveness of Problem-Based Learning (PBL) instructional videos in improving students’ conceptual understanding. The research employed a Research and Development approach using the ADDIE model and adopted a pre-experimental design with a one-group pretest–posttest involving 36 students as trial subjects. The instruments included expert validation sheets, conceptual understanding tests, and student response questionnaires. Data were analyzed using descriptive statistics, normality tests, paired-sample t-tests, and N-Gain analysis. The results showed that the instructional video product was categorized as highly feasible based on expert validation and student responses (89.7%). The students’ mean scores increased from 57.97 to 69.44, with a reduction in variance and standard deviation, indicating a more even distribution of conceptual understanding. The normality test confirmed that the data were normally distributed, and the paired-sample t-test revealed a significant difference between pretest and posttest scores (p < 0.001). The N-Gain value of 0.27 was in the low–moderate category, indicating initial effectiveness. Therefore, the developed PBL instructional videos indicate initial effectiveness in enhancing students’ conceptual understanding and can be considered a feasible instructional innovation for junior secondary school physics learning.

Keyword: learning video, Problem-Based Learning, conceptual understanding, junior high school physics, instructional innovation

IMPROVING INFORMATICS STUDENTS’ MATRIX ALGEBRA CONCEPTUAL UNDERSTANDING THROUGH A PYTHON-BASED LEARNING TRAJECTORY

Syelfia Dewimarni, Elmi Rahmawati, Lili Rismaini — Tue, 10 Mar 2026 00:00:00 +0700

In matrix algebra courses, conceptual understanding remains low. This is due to the lack of integration and relevance of mathematics learning to their competency, namely informatics engineering. Learning trajectory instruction, characterized by sequential learning and Python computing applications relevant to students, provides a solution to improve students' matrix algebra conceptual understanding. The purpose of this study was to examine students' understanding of mathematical concepts in algebra by implementing a Python-based learning trajectory model. This study was a quasi-experimental study with posttest-only control group design. The sample was taken using a random sampling technique. A sample size of 69 students was selected, consisting of 33 students from the experimental class and 36 students from the control class. The results of this study present the difference in the average test scores for understanding matrix algebra concepts between the experimental and control classes. The t-test showed that t-test (3.469) > t-table (1.997), with α = 0.05 (df = 67), indicating that H₁ was accepted, stating that the Python-based Learning trajectory model is effective as an alternative learning strategy to strengthen students' matrix algebra conceptual understanding.

Keywords: Learning Trajectory; Python; Conceptual Understanding; Matrix Algebra

COLLABORATIVE LEARNING APPROACH TO MASTER KPK AND FPB CONCEPTS

Zihan Nur Halizah, Luthfi Hamdani Maula, Efi Kurniasari — Tue, 10 Mar 2026 00:00:00 +0700

This research seeks to improve students' understanding of KPK and FPB concepts at SDN Cemerlang by addressing the constraints associated with the use of concrete media in mathematics instruction. Through the ADDIE model R&D method, Dakonball media based on Collaborative Learning was developed with 40 students. The validation results of material experts (93%), media (100%), and practitioners (93%) stated that the product is very feasible. The implementation showed a significant increase in learning outcomes, from an average of 35.13 pre-tests to 83.19 in the post-test. The results of the Paired Sample T-Test showed a significance value of 0.000, which is below the significance threshold (α = 0.05). With an N-gain of 0.73 (high category) and a positive response from students (90%), Dakonball media proved to be valid, practical, and statistically effective as an interactive mathematics learning solution in elementary schools.

Keywords: Collaborative Learning; Dakonball; KPK and FPB; Elementary School

ETHNOMATHEMATICS-BASED COGNITIVE ASSESSMENT MODEL FOR DYSCALCULIA STUDENTS

Gebby Kusuma Rahayu, Kamid, Yelli Ramalisa — Tue, 10 Mar 2026 00:00:00 +0700

This research is motivated by the learning difficulties experienced by students with dyscalculia in mathematics, particularly in understanding numerical concepts and performing basic arithmetic operations. This study aims to develop an ethnomathematics-based cognitive assessment model using the traditional congklak game and question cards to assess students' cognitive abilities in learning mathematics. This study uses the Research and Development (R&D) method with the ADDIE model, which consists of five stages: Analysis, Design, Development, Implementation, and Evaluation. The research participants were six seventh-grade students with dyscalculia identified through a screening test. The developed model was tested with content validity and reliability tests. Content validity was validated by two experts, namely a subject matter expert and a media design expert, to evaluate the content and feasibility of the assessment model design. The results showed that the model achieved a validity score of 96.88% from the media expert and 93.75% from the subject matter expert, indicating that the product is valid. Furthermore, the reliability test using Inter-Rater Reliability (ICC) produced a value of 0.892, indicating very high reliability. These findings suggest that an ethnomathematics-based cognitive assessment model can be used as an alternative tool to assess the cognitive abilities of students with dyscalculia in adding and subtracting integers through culturally relevant learning activities.

Keywords: Assessment cognitive; Ethnomathematics; Dyscalculia; Congklak

EXPLORING STUDENT PERCEPTIONS: VISUALIZING ABSTRACT CONCEPTS IN DESCRIPTIVE GEOMETRY USING GEOGEBRA

Aris Hadiyan Wijaksana, Yaya Sukjaya Kusumah, Turmudi — Tue, 10 Mar 2026 00:00:00 +0700

Descriptive Geometry is a fundamental course that demands high-level spatial visualization skills, where students often face significant cognitive challenges in projecting three-dimensional (3D) objects onto two-dimensional (2D) planes using conventional methods. This study aims to deeply explore student perceptions regarding the use of the dynamic geometry software GeoGebra as a medium for visualizing abstract concepts in this course. Using a qualitative case study approach, this research involved 13 students from the mathematics education program at Universitas Negeri Jakarta. Data were collected through semi-structured interviews and analyzed using thematic analysis. The findings indicate that students perceive GeoGebra as a transformative pedagogical tool. Four main themes were identified: (1) GeoGebra serves as a conceptual bridge that translates abstract concepts into concrete and dynamic visual representations; (2) GeoGebra's interactive environment is considered far superior to the static paper-and-pencil method, offering accuracy, efficiency, and freedom to experiment; (3) The use of GeoGebra shifts the student's role from a passive recipient to an active learner engaged in independent exploration; and (4) Despite an initial learning curve, the challenge of mastering the software fosters the development of student agency and learning autonomy. This study concludes that GeoGebra effectively reduces the cognitive load associated with spatial visualization and enhances student engagement and conceptual understanding. The implications of these findings underscore the importance of planned technological integration into advanced geometry curricula to facilitate more meaningful learning.

Keywords: Descriptive Geometry; GeoGebra; Spatial Visualization; Student Perceptions; Dynamic Geometry Software