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All Journal Jurnal Pendidikan Vokasi Jurnal Elemen JCES (Journal of Character Education Society) JKPM (Jurnal Kajian Pendidikan Matematika) FIBONACCI: Jurnal Pendidikan Matematika dan Matematika GAUSS: Jurnal Pendidikan Matematika Arithmetic : Academic Journal of Math Jurnal Lebesgue : Jurnal Ilmiah Pendidikan Matematika, Matematika dan Statistika Koordinat : Jurnal Pembelajaran Matematika dan Sains Plusminus: Jurnal Pendidikan Matematika Jurnal Didactical Mathematics Jurnal Pengabdian Mandiri JURNAL INOVASI DAN MANAJEMEN PENDIDIKAN
Lestari, Indri
Universitas Serang Raya
Humanities Decision Sciences, Operations Research & Management Education Languange, Linguistic, Communication & Media Mathematics Physics Social Sciences Other

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Integration of item response theory in the development of PhET-based graphing lines worksheets for optimizing student algebra competence Giyanti; Lestari, Indri; Oktaviyanthi, Rina
Jurnal Elemen Vol 11 No 1 (2025): January
Publisher : Universitas Hamzanwadi

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29408/jel.v11i1.27634

Abstract

This study develops and evaluates a graphing line worksheet based on PhET Interactive Simulation integrated with Item Response Theory (IRT) methods to enhance student algebra competence. Involving 120 students, the worksheet comprises 12 items measuring four key indicators: understanding the geometric significance of line slopes, constructing line equations, graphing from line equations, and predicting the effects of variable changes. The 2-Parameter Logistic (2PL) model of IRT was employed to analyze item difficulty and student ability in logit form. The results indicate that the worksheet is effective in improving student algebra competence, with Items 1 and 11 demonstrating a good balance between difficulty and discrimination. Item 2 requires further review because of its high difficulty, whereas Item 12 is considered too easy. Heatmap analysis and Item Characteristic Curves (ICC) revealed variations in student response patterns, confirming the test's ability to evaluate diverse levels of student ability. The integration of interactive simulation and IRT has proven to be an effective strategy in instructional design, supporting adaptive and personalized learning.
Mathematical Engagement In Interactive Learning: A Case Study Of The Use Of Lumio In Understanding The Concept Of Normal Distribution Lestari, Indri; Hadi, Windia; Giyanti, Giyanti; Khotimah, Khotimah
Koordinat Jurnal MIPA Vol. 6 No. 2 (2025)
Publisher : Program Studi Tadris Matematika dan Tadris Ilmu Pengetahuan Alam, Fakultas Tarbiyah dan Ilmu Keguruan (FTIK), Universitas Islam Negeri (UIN) Datokarama Palu

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24239/koordinat.v6i2.192

Abstract

Understanding the concept of normal distribution in statistics is often challenging for students, as it requires a deep understanding of symmetry, probability distribution, and the use of normal distribution tables. These challenges are often caused by difficulties in connecting theoretical concepts with data visualization and in comprehending z-score transformations. This study aims to analyze students' mathematical engagement in understanding the concept of normal distribution using Lumio-based interactive media. The study employed a quantitative, quasi-experimental design, with a pre-test post-test control group design. The experimental group engaged in learning using Lumio-based interactive media, while the control group received traditional lecture-based teaching methods. The research instruments included a concept comprehension test, a mathematical engagement questionnaire, and an analysis of Lumio activity logs. The data were analyzed using paired sample t-tests and ANCOVA to evaluate the effectiveness of Lumio in improving students' mathematical engagement and conceptual understanding. The results showed a significant difference between pre-test and post-test scores in both the experimental and control groups. The experimental group, which used Lumio, showed a significantly higher improvement in both conceptual understanding and engagement compared to the control group. The findings suggest that using Lumio-based learning significantly enhanced students' engagement and understanding of normal distribution, compared to the conventional teaching methods
Enhancing Students’ Self-Confidence In Mathematics Through Geogebra-Assisted TAPPS Indri Lestari; Rina Oktaviyanthi; Tb. Sofwan Hadi; Nagina Slavina
Koordinat Jurnal MIPA Vol. 7 No. 1 (2026)
Publisher : Program Studi Tadris Matematika dan Tadris Ilmu Pengetahuan Alam, Fakultas Tarbiyah dan Ilmu Keguruan (FTIK), Universitas Islam Negeri (UIN) Datokarama Palu

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24239/koordinat.v7i1.201

Abstract

This study aimed to investigate the effectiveness of GeoGebra-assisted Thinking Aloud Pair Problem Solving (TAPPS) in improving students’ self-confidence in mathematics learning. The study employed a quantitative approach using a quasi-experimental method with a non-equivalent control group design. The participants consisted of 70 eleventh-grade students from a public senior high school in Tangerang, Indonesia, selected through purposive sampling. The sample was divided into an experimental group and a control group, each consisting of 35 students. Data were collected using a self-confidence questionnaire comprising 30 statements based on four dimensions of self-confidence: belief in one’s own abilities, positive thinking and action, optimism and perseverance, and adaptability and social interaction. The data were analyzed using descriptive statistics, normality and homogeneity tests, an independent samples t-test, and N-gain analysis. The results revealed that the experimental group demonstrated greater improvement in self-confidence than the control group. Although the post-scale comparison did not indicate a statistically significant difference between groups (p = .060), the N-gain analysis showed a significant difference in improvement (p = .001). These findings suggest that GeoGebra-assisted TAPPS contributes positively to the development of students’ self-confidence and facilitates greater growth in confidence throughout the learning process. Therefore, the integration of collaborative problem-solving strategies and dynamic mathematical visualization can be considered a promising approach for promoting positive affective outcomes in mathematics learning
Cognitive apprenticeship in vocational students mathematical decision making skills Rina Oktaviyanthi; Indri Lestari
Jurnal Pendidikan Vokasi Vol. 13 No. 1 (2023)
Publisher : ADGVI & Graduate School of Universitas Negeri Yogyakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21831/jpv.v13i1.52831

Abstract

Exploring the decision-making abilities of undergraduate students, including students from vocational education backgrounds, is the main priority in the achievement of mathematics learning in general and in Calculus courses particularly. Decision-making processes require cognitive guidance through activities describing in detail the systematic steps of each process. It is implicitly said as part of a cognitive apprenticeship procedure. There are claims that students with a vocational education background can develop their academic and practical potential more through a cognitive apprenticeship model. In addition, using video as visual media learning allows students to sharpen their skills. Therefore, the study aims to explore the distinction in achievement and improvement of mathematical decision-making skills between undergraduate students who learn with a Video-assisted Cognitive Apprenticeship approach (CAV), and they are who receive Cognitive Apprenticeship learning (CA) with conventional learning. A quantitative study with the Static-Group Pretest-Posttest Design was employed as a methodology in the research. Based on the research stage, there are differences in achievement and improvement of student decision-making skills with a review of the type of vocational school between undergraduate students.
Improving university students’ geometrical understanding of derivatives through graphic visualization Khotimah Khotimah; Indri Lestari; Ria Noviana Agus; Rina Oktaviyanthi; Shila Panca Putri; Semiha Kula Ünver
Jurnal Elemen Vol 12 No 1 (2026): January
Publisher : Universitas Hamzanwadi

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29408/jel.v12i1.33325

Abstract

This study addresses university students’ persistent difficulties in developing geometrical thinking, defined as the ability to interpret slopes, understand tangent behavior, and coordinate graphical and symbolic representations, when learning derivative concepts. The study investigates changes in students’ geometrical thinking following instruction supported by graphic visualization. A one-group pretest–posttest quasi-experimental design was conducted with 30 students in mathematics education, limiting causal inference due to the absence of a control group. Data were collected using a six-item open-ended geometrical thinking test and structured classroom observations, which served as triangulation. The results showed significant improvement after the visualization-based instruction. The average pretest score increased from 48.12 to 67.51, with a normalized gain (N-gain) of 0.39, indicating moderate improvement. A paired-sample t-test confirmed a statistically significant difference (p < 0.001). Although the effect size was large (d = 4.17), this finding should be interpreted cautiously given the study design and sample size. Observation data supported these results by revealing improved graphical reasoning, representational coordination, and student engagement. These findings indicate the potential of graphic visualization to support students’ geometrical thinking in derivative learning, rather than to demonstrate definitive instructional effectiveness.
Co-Authors Ami Fidianty Chatarina Umbul Wahyuni Devy Permatasari Eva Fitria Ningsih Giyanti Giyanti, Giyanti Hadi, Tb Sofwan Ken Ima Damayanti Khotimah Khotimah Khotimah Khotimah Nagina Slavina Ria Noviana Agus Rina Oktaviyanthi, Rina Semiha Kula Ünver Shila Panca Putri Sofwan Hadi, Tb. Supriani, Yani T.S. Hadi Tebe Sofwan Wian Azrilia Windia Hadi, Windia Yunita Kusumawati