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Sufyani Prabawanto, Sufyani

Indonesia University Of Education

Author-ID : 580979

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The Mechanism of Didactical Obstacles in the Pythagorean Theorem: From Visual Rigidity to Procedural Failure Dahlan, Jarnawi Afgani; Prabawanto, Sufyani; Bariyah, Nusrotul; Nti, Seth Junior
Jurnal Pendidikan MIPA Vol 26, No 4 (2025): Jurnal Pendidikan MIPA
Publisher : FKIP Universitas Lampung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.23960/jpmipa.v26i4.pp2495-2517

Learning the Pythagorean theorem is a significant challenge at the junior high school level because students often struggle to understand concepts, connect geometric and algebraic representations, and solve contextual problems. Based on previous studies, students' difficulties indicate the presence of learning obstacles. Existing research has addressed students' difficulties, errors, and epistemological obstacles in solving Pythagorean theorem problems and has presented applications of the Pythagorean theorem. Therefore, this study aims to analyze students' didactic learning obstacles to the Pythagorean theorem topic. To achieve this goal, a qualitative case study was conducted. Data was collected through data triangulation: written tests, interviews, and document studies. At the data-collection stage, 30 students and two teachers participated. Based on the written test results, the answers exhibit various characteristics. At the analysis stage, it is performed using ATLAS.ti software. The results show that there is a form of didactic learning obstacles consisting of visual orientation obstacles and formula procedural obstacles. The Visual orientation obstacles include students' lack of understanding of triangle concepts. The procedural obstacles include students' incomprehension of algebraic representations, understanding of problem-solving, understanding of procedures beyond integers, and application of Puythagos' theorem formulas. Visual orientation obstacles cause formula procedural obstacles. The didactic factor that creates obstacles is the way the topic is presented and the teacher's approach to designing learning. Didactic obstacles analysis is an important step in formulating a hypothesis about how a concept should be taught. By knowing the didactic obstacles, teachers or researchers can develop a more accurate Hypothetical Learning Trajectory (HLT). This will lead to the design of learning activities that anticipate common mistakes and misconceptions. Keywords: didactical obstacle, learning obstacle, topic presentation analysis, textbooks, pythagorean theorem.

Investigating Students’ Mathematical Literacy in PISA Tasks Using Newman’s Theory Wahyudi, Dwi Arisma; Prabawanto, Sufyani
IndoMath: Indonesia Mathematics Education Vol 9, No 1 (2026): Vol 9 No 1, February 2026
Publisher : Universitas Sarjanawiyata Tamansiswa

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30738/indomath.v9i1.175

This study investigates the gap between technological ubiquity and stagnant mathematical literacy among Indonesian students. The research objective was to identify and analyze specific cognitive hurdles hindering students’ ability to solve contextual, PISA-adapted problems. Utilizing a qualitative descriptive design, the study involved 34 ninth-grade students in Kabupaten Bandung Barat. Subjects for semi-structured interviews were selected via purposive sampling, targeting those demonstrating representative error patterns across high, moderate, and low proficiency tiers. Data were analyzed using Newman’s Error Analysis (NEA) and validated through methodological triangulation. Results revealed that 52.94% of students possess low mathematical literacy, with the most critical barrier being transformation errors (58.36%), followed by comprehension (27.94%) and reading (14.70%). Qualitative findings indicate that these errors stem from three primary factors: contextual unfamiliarity with non-routine tasks, a detrimental dependency on teacher scaffolding, and conceptual deficits in processing decimal notation. The study concludes that students struggle to bridge the gap between narrative contexts and mathematical formalization. To mitigate these barriers, the research recommends the implementation of incremental scaffolding and explicit instructional strategies focusing on linguistic-to-mathematical translation to foster learner autonomy and higher-order thinking skills in the Indonesian educational framework.

(RE)CONCEPTUALIZING LINEAR EQUATIONS: A SNAPSHOT FROM TEACHING AND LEARNING IN INDONESIA Fardian, Dilham; Suryadi, Didi; Prabawanto, Sufyani; Jupri, Al
Jurnal Ilmiah Ilmu Terapan Universitas Jambi Vol. 9 No. 3 (2025): Volume 9, Nomor 3, September 2025
Publisher : LPPM Universitas Jambi

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22437/jiituj.v9i3.37450

This study aimed to describe the zone of concept image differences in linear equations in one variable and analyze its potential impact on mathematics learning. This research was qualitative and followed a phenomenological approach. Mathematical praxeology was used to analyze the content of the knowledge to be taught (Indonesian curriculum). In contrast, didactic praxeology was used to analyze the teaching methods involved in the taught knowledge (teacher). This study explores information obtained from human and non-human sources. The object of the study was a seventh-grade mathematics textbook used in Indonesian middle schools, which refers to the Merdeka curriculum. The results showed differences in concept image between scholarly knowledge, knowledge to be taught, and knowledge regarding the topic of linear equations in one variable. Teachers failed to understand the information provided in the mathematics textbook that the equal sign in the concept of a linear equation in one variable represents a quantitative equation, meaning the expression on the left side of the equal sign is equal to the expression on the right side of the equal sign. This research presents an alternative praxeological reference model as an implication for the field of education in Indonesia, allowing students to generate new knowledge as justified true belief independently. Policymakers can also utilize the model to design linear equations in one variable materials that are more aligned with students' abilities by providing a structured approach that takes into account the students' prior knowledge and learning pace.

How High School Students Solve Proportional Reasoning Problem? Ahmad Zulfa Khotimi; Sufyani Prabawanto; Al Jupri
Didaktik Matematika Vol 11, No 1 (2024): April 2024
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jdm.v11i1.36458

This research is motivated by the phenomenon of students' difficulties in solving proportional reasoning problems and the lack of proportional reasoning research at the high school level. This research aims to describe in depth the ability of high school students to solve proportional reasoning problems and learning obstacles that may occur. The method used is qualitative with a case study approach. The research subjects involved were 5 students from grades 10 to 12. The instruments used were tests and interview guides. The research results showed that there were 4 mistakes made by students in solving proportional reasoning problems, namely (1) Using the additional strategy in solving proportional reasoning problems; (2) Not being able to solve problems of indirect proportion; (3) Using multiplication strategies in solving non-proportional problems; and (4) Not being able to compare ratios. Concerning learning obstacles, there are 2 types of learning obstacles that are indicated to be experienced by students, namely epistemological obstacles and ontogenic obstacles. The results of this research can be used as a basis for carrying out further research in the form of research that designs learning flows and/or learning designs that can develop students' proportional reasoning abilities.

Exploring Students Mathematical Understanding according to Skemps Theory in Solving Statistical Problems Christina Monika Samosir; Jarnawi Afgani Dahlan; Tatang Herman; Sufyani Prabawanto
Didaktik Matematika Vol 10, No 2 (2023): October 2023
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jdm.v10i2.32598

Understanding a concept is not only for mastering the next concept. It is the foundational skill used to solve mathematical problems. This study aims to explore students' conceptual understanding.This research is qualitative research with phenomenology. The participants in this study consisted of 18 eighth-grade students from one of Bandung's private secondary schools. After the students were given the test, six students were selected as research subjects. This aims to ensure that data can be obtained thoroughly and comprehensively. Data collection techniques included tests, interviews, and observations, with research instruments comprising a test and an interview guideline. Data saturation has been achieved. The results of this study are as follows: 1) students with relational understanding are fewer in number than students with instrumental understanding. 2) students find it most difficult to use the interconnections of various mathematical concepts in solving problems. 3) students' difficulties are due to their lack of ability in the concept of basic operations and their lack of understanding of the problems. Therefore, teachers need to strengthen students' understanding of basic operations and the concepts of mean, mode, and median to effectively connect these concepts with their problems.

Zone of Concept Image Differences in Infinite Limits at Undergraduate Level Rini Sulastri; Didi Suryadi; Sufyani Prabawanto; Endang Cahya; Fitriani Fitriani
Didaktik Matematika Vol 9, No 1 (2022): April 2022
Publisher : Universitas Syiah Kuala

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24815/jdm.v9i1.24709

The gap between the concept image and the concept definition will greatly affect a persons understanding of the concept. This study aims to reveal the gap between the concept image and the concept definition, and the causes of the emergence of the gap. The research subjects were 16 first-year mathematics students at one of the universities in Aceh, Indonesia. Data were obtained from the results of written tests and in-depth interviews. This qualitative research with a phenomenological study approach was analyzed descriptively. The results showed that the gap that occurs in the concept includes: the division of a non-zero number by zero yields infinity, the concept of dividing zero by zero is zero, the concept of dividing a number by zero is the same as the concept of the limit, e.g., , and the concept of the left-hand limit as means that the satisfied value of x is all negative numbers such that . The emergence of these concept images results from the subject's learning experience at school and a calculus course. This finding provides insights and considerations for educators to comprehensively introduce students to the concept of infinity to avoid misunderstandings in limit and next materials.

How to construct theorems of parallelism condition? A study of learning obstacles and GeoGebra-based didactical design Herizal; Priatna, Nanang; Prabawanto, Sufyani; Jupri, Al
Journal on Mathematics Education Vol. 17 No. 1 (2026): Journal on Mathematics Education
Publisher : Universitas Sriwijaya in collaboration with Indonesian Mathematical Society (IndoMS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22342/jme.v17i1.pp277-298

In Euclidean geometry, parallelism constitutes a foundational concept from which numerous geometric ideas are derived. Despite its fundamental role in geometry and its importance in developing deductive and logical reasoning, research on the concept of parallelism—particularly concerning students’ learning obstacles and corresponding didactical approaches—remains limited, especially in higher education contexts. This study investigates the construction of theorems related to parallelism conditions by examining learning obstacles and implementing a GeoGebra-based didactical design within the framework of the Theory of Didactical Situations. Employing a qualitative approach with a phenomenological hermeneutic design, the study involved 64 undergraduate students from the Mathematics Education Department of a public university in Aceh, Indonesia, to identify the learning obstacles, and 35 students who participated in the implementation of the designed instructional intervention. Data were collected through document analysis, interviews, classroom observations, and audio–video recordings. The data analysis followed the three stages proposed by Miles and Huberman: data reduction, data display, and conclusion drawing. The findings revealed that students’ understanding of the theorems concerning parallelism conditions was impeded by three primary types of learning obstacles: epistemological, didactical, and ontogenic. To address these challenges, a GeoGebra-based didactical design was developed and implemented. The results demonstrated that this design effectively mitigated the identified obstacles and facilitated students’ construction of the theorems of parallelism conditions. Furthermore, the implementation appeared to foster a gradual shift in students’ learning orientation from procedural toward conceptual understanding, although this transition was not entirely uniform. Finally, the study highlights the pedagogical significance of integrating didactical situation theory into the learning process and employing dynamic visualization tools such as GeoGebra to support the transition from empirical to deductive mathematical reasoning.

How do students solve critical thinking tasks in trigonometry? A qualitative analysis of critical thinking skills Aridanthy, Vanya; Kusumah, Yaya S.; Dahlan, Jarnawi Ahmad; Prabawanto, Sufyani; Melati, Catur Yustika
Indonesian Journal of Science and Mathematics Education Vol. 9 No. 1 (2026): Indonesian Journal of Science and Mathematics Education
Publisher : Universitas Islam Negeri Raden Intan Lampung

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.24042/ijsme.v9i1.25867

Critical thinking skills are crucial for students to analyze and solve problems effectively, yet many still struggle in apply them comprehensively. This study aimed to examine students' critical thinking skills using a qualitative descriptive approach. The study used an essay-based assessment developed based on the framework of Perkins and Susilo et al., which includes four main indicators: clarification, judgment, inference, and strategy development. The findings indicated that students demonstrated partial critical thinking skills; most could analyze or clarify problems, while some could present problems with reasoning or examples and draw compelling conclusions. However, many students still struggled to develop effective problem-solving strategies. These results imply the need for improved instruction that places greater emphasis on strengthening problem-solving skills to enhance students' overall critical thinking skills.

Efektivitas Metode GASING Dalam Meningkatkan Numerasi Guru dan Siswa di Daerah 3T Melisa, Melisa; Prabawanto, Sufyani; Mulyasari, Effy; Surya, Marcia Ann
Mimbar PGSD Flobamorata Vol. 4 No. 2 (2026): MIMBAR PGSD FLOBAMORATA
Publisher : Program Studi Pendidikan Guru Sekolah Dasar-Universitas Muhammadiyah Kupang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.51494/mpf.v4i2.3242

Abstrak: Penelitian ini bertujuan untuk menganalisis efektivitas Metode GASING (Gampang, Asik, dan Menyenangkan) dalam meningkatkan kompetensi numerasi guru dan siswa di Kabupaten Teluk Wondama, Papua Barat sebagai salah satu daerah Terdepan, Terluar, dan Tertinggal (3T) di Indonesia. Penelitian menggunakan pendekatan kuantitatif dengan desain pre-eksperimental tipe one-group pretest-posttest. Subjek penelitian terdiri atas 46 guru dan 96 siswa sekolah dasar yang mengikuti program intensif selama tiga minggu (10–30 Juni 2025). Instrumen penelitian berupa tes tertulis yang mengukur lima kompetensi dasar berhitung, yaitu Bakal Kubagi, penjumlahan, perkalian, pengurangan, dan pembagian. Hasil penelitian menunjukkan peningkatan yang signifikan, ditandai dengan kenaikan rata-rata skor guru dari 32,33 menjadi 79,83 dengan nilai N-Gain sebesar 0,702 (kategori tinggi), serta peningkatan rata-rata skor siswa dari 10,51 menjadi 75,51 dengan nilai N-Gain sebesar 0,727 (kategori tinggi). Hasil uji Paired Sample t-Test menunjukkan perbedaan yang signifikan secara statistik (α = 0,05) pada seluruh kompetensi yang diukur. Temuan ini menunjukkan bahwa Metode GASING efektif dalam meningkatkan kemampuan numerasi melalui pendekatan bertahap konkrit–abstrak–komputasi mental yang dikemas secara interaktif dan menyenangkan. Penelitian ini memberikan kontribusi empiris bagi pengembangan kebijakan pendidikan berbasis bukti di daerah 3T, serta menegaskan pentingnya intervensi terpadu yang menyasar guru dan siswa dalam satu ekosistem pembelajaran. Abstrak: This study aims to analyze the effectiveness of GASING Method (Easy, Fun, and Enjoyable) in improving numeracy competencies among teachers and students in Teluk Wondama Regency, West Papua one of Indonesia's underdeveloped frontier regions. Using a quantitative approach with a pre-experimental one-group pretest-posttest design, the study involved 46 teachers and 96 students from various primary schools who participated in a three-week intensive program (10–30 June 2025). The research instruments consisted of written arithmetic tests covering five core competencies: Basic Number Sense (Bakal Kubagi), Addition, Multiplication, Subtraction, and Division. Results demonstrated highly significant improvements: teachers' mean scores increased from 32.33 (pre-test) to 79.83 (post-test) with an N-Gain of 0.702 (High category), while students' mean scores rose from 10.51 (pre-test) to 75.51 (diagnostic test) with an N-Gain of 0.727 (High category). Paired Sample t-Test analyses revealed statistically significant differences (α = 0.05) across all measured competencies. Both groups' N-Gain scores substantially exceeded the international average of 0.34 reported in comparable intervention studies (Westphale et al., 2022). These findings demonstrate that the GASING Method with its sequential concrete–abstract–mental computation approach delivered through playful, interactive activities is an effective and replicable solution for addressing the numeracy crisis in Indonesia's remote regions. This research contributes to evidence-based education policy development in underserved areas and reinforces the importance of integrated interventions targeting both teachers and students simultaneously within a unified learning ecosystem.

Eksplorasi kesalahan siswa kelas X dalam menyelesaikan soal eksponen dan logaritma berdasarkan kategori Watson Nurhayati, Ani; Prabawanto, Sufyani; Novianingsih, Khusnul
JPMI (Jurnal Pembelajaran Matematika Inovatif) Vol. 9 No. 1 (2026): JPMI
Publisher : IKIP Siliwangi

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22460/jpmi.v9i1.29615

The high level of students’ errors in solving problems on exponents and logarithms indicates the presence of conceptual difficulties that need to be analyzed systematically. This study aims to analyze high school students’ errors on exponents and logarithms. The research was conducted on tenth-grade students at a senior high school in Bandung, involving 20 students, from which 6 samples were randomly selected. This study employed a qualitative approach with a descriptive method. The research instrument consisted of validated exponent and logarithm problems. The results showed that, based on the percentage of students’ errors in solving mathematical problems according to Watson’s error categories, inapproriate procedure errors were classified as high, reaching 48%. Omitted data errors were categorized as low at 14%, and response level conflict errors were also categorized as low at 10%. Skill hierarchy errors were classified as very low at 5%. Errors outside the seven categories were categorized as low at 24%. Meanwhile, incorrect data errors, omitted conclusion errors, amd undirected manipulation errors were not found (0%), thus falling into the very low category.

Co-Authors A.A. Ketut Agung Cahyawan W Abdul Mujib Aflich Yusnita Fitrianna Agung Wicaksono Ahmad Arifuddin Ahmad Nizar Rangkuti Ahmad Tafsir Ahmad Tafsir, Ahmad Ahmad Zulfa Khotimi Ahmad Zulfa Khotimi Ahmatika, Deti Aiyub Aiyub Alfitri, Putri Armania Agustina Alman Alman Alman Alman, Alman Amalia Indrawati G Andika Putra R Aneu Pebrianti Anwar, Agus Saeful Aridanthy, Vanya Aryanti Asep Syarif Hidayat Asfar, A.M.Irfan Taufan Asfar, Andi Muhamad Iqbal Akbar Aswin Aswin Atep Sujana Augie, Kintan Tyara Bambang Eko Susilo Bambang Hariyomurti Bariyah, Nusrotul Candra Nugraha Cece Kustiawan Cecep Anwar Hadi Firdos Santosa Cecep Anwar Santosa Christina Monika Samosir Citra Utami Dadan Dasari Dadan Hermawan, Dadan Dadang Juandi Dahlan, Jarnawi Ahmad Dallyono, Ruswan Darhim Darhim David Nurfiqih Dela Ambarwati Desi Elizanti Desy Lusiyana Dewi Nurmalitasari Dian Cahyawati Dian Nopiyani Dian Usdiyana Didi Suryadi Didi Suryadi Didi Suryadi Dinar Nur Alkifah Jihadatunnafsy Doni, Petrus Kanisius Nama Dwi Arisma Wahyudi Edi Irawan Edria Al Shahada Effy Mulyasari Ejen Jenal Mutaqin Eka Novarina EKO YULIANTO Eko Yulianto Eko Yulianto Elah Nurlaelah Elizanti, Desi Encum Sumiaty, Encum Endang Cahya Mulyaning A. Eyus Sudihartinih Fardian, Dilham Fathiyah, Ifa Fatimah Aqilah Ichtiari Fatimah, Siti Febriani, Winarti Dwi Fitri Ayu Febrianti Fitri Ayu Febrianti Fitriana Lestari Fitriani Fitriani Fujiarti, Ari Ginda M.A.Siregar Gita Rani Putri Mangiri Gumpita, Melly Terry Gunadi, Farid Hadi Haeruddin, Haeruddin Hani Nurhasanah Hayuningrat, Silfia Herizal Herizal Hutkemri Zulnaidi Iden Rainal Ihsan Ifa Fathiyah Inayah, Sarah Indiana Marethi Indiana Marethi, Indiana Indra Nurhidayat Irena Puji Luritawaty Istikomah, Endang Itoh Masitoh Izzy Balagtas Villarico Jarnawi Afgani Dahlan Jozua Sabandar Jurpri, Al Jusniani, Nia Kartika Yulianti Kholipah, Nuzuliah Khotimah, Wonadesma Dwi Khusnul Novianingsih Kintan Tyara Augie Kurniawati, Ririn Laelasari Laelasari, Laelasari Lien Malinda Lina Siti Nurwahidah Lucky Heryanti Jufri Lukman Lukman M Akbar Gulvara M Candra Nugraha Deni Mangiri, Gita Rani Putri Masitoh, Lisda Fitriana May Nisa Istiqomah Mefiana, Syifa Ananda Meicindy Jeny Klorina Meilani, Rini Melani, Rini Melati, Catur Yustika Melisa Melisa Milah Nurkamilah Mimi Hariyani Mohamad Gilar Jatisunda Muhamad Soeleman Muhamad Yasin Mustika Fauziah, Hilma Nabila Cynthia Rayhan Nanang Priatna Nandang Arif Saefuloh Nazla Nurul Aulia Panggabean Nelvita Febrina Hasan ningrum, yunia jumita Nopiyani, Dian Nopiyani, Dian Nova Nurhanifah Novi Andri Nurcahyono Novia Rahmi Noviana Antaria Nti, Seth Junior Nuaini, Intan Nuke Fitri Yanuari Nur Qamariah Nurannisa, Andi Nurdiyah Kurniati Nurhayati, Ani Permani, Kania Dewi Pertiwi, Saffanah PRASETYAWAN, ENGGAR Prihandhika, Aditya Putri, Amelia Defrianti Rachmawati Khaerun Nisa Raisya Hizkiya Syabina Ramli Ramli Rani Sugiarni Rini Sulastri Riny Arviana Ririn Kurniawati Riza Fatimah Zahrah Rizki, Raihan Ahmil Rizky Rosjanuardi Rohimah, Siti Maryam Rosmayasari Rosmayasari Rosmayasari, Rosmayasari Rostina Sundayana Rusdiono Muryanto Ruswan Dallyono Saefuloh, Nandang Arif Saefuloh, Nandang Arif Safrina Safrina Samosir, Christina Monika Sandra Sukmaning Adji Santi, Eneng Sanusi Sanusi Saputra, Samnur Sarassanti, Yumi Sarnav Ituga, Almuhaimin Sendi Ramdhani Septian, Ari Simanjuntak, Sinitta Marito Siregar, Rama Nida Sitanggang, Damra Ali Siti Fatimah Siti Zakiyah Sofa, Rostika Nurlaela Nova Maya Suhendra Suhendra Suhendra, S Sukma Murni Sukri Sukri suparni Surya, Marcia Ann Syamsuri Syamsuri Syarifah, Mufarrahatus Syarifah, Mufarrahatus Syifa Ananda Mefiana Tata Frarisia Tatang Herman, Tatang Tin Lam, Toh Trisna Nugraha Trisnowali MS, Andi Turmudi Ulfah Nur Azizah Ulfah Nur Azizah Umbara, Uba Umbara, Uba Usep Kosasih Wafa Islamiyah Wahyu Hidayat Wahyu Sopandi Wahyudi, Dwi Arisma Wahyudin Wahyudin Wahyudin Wahyudin Wahyudin Wahyudin Wahyudin Wardani, Ambarsari Kusuma Wenda Alifulloh Widdy Sukma Nugraha Yasin, Muhamad Yaya S. Kusumah Yeni Dwi Kurino Yeni dwi Kurino Yusuf Adhitya

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