Jurnal Pijar MIPA (e-ISSN: 2460-1500 & p-ISSN: 1907-1744) is an open-access, peer-reviewed scientific journal published by the Department of Mathematics and Science Education, Faculty of Teacher Training and Education, University of Mataram. The journal publishes original research articles and reviews encompassing various topics in natural sciences and science education, particularly in Physics, Chemistry, and Biology.
Department of Mathematics and Science Education, Faculty of Teacher Training and Education, University of Mataram. Jurnal Pijar MIPA colaborates with Perkumpulan Pendidik IPA Indonesia Wilayah Nusa Tenggara Barat
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Development of an E-Module Assisted by Augmented Reality on Digestive System Material to Improve Elementary Students' Critical Thinking Skills
Digital teaching materials, such as e-modules in basic science that utilise technology, have not yet been implemented in learning, resulting in 56% of students having low critical thinking skills. This study aims to describe the development design and to test the feasibility and effectiveness of an Augmented Reality-assisted e-module to improve the critical thinking skills of V-grade students at SDN Pendrikan Lor 03, Semarang City. This type of research is Research & Development (R&D) with the ADDIE development model (Analysis, Design, Development, Implementation, and Evaluation). The research subjects were 25 V-grade students. The data collection technique used non-test methods (observation, interviews, questionnaires, and documentation) and test methods (pretest and posttest). The data analysis technique used normality tests, homogeneity tests, t-tests, and N-Gain tests. The feasibility of the e-module assisted by Augmented Reality is proven by the assessment of the material expert validator of 91% and the media expert validator of 95% in the very feasible category, supported by the results of the teacher response questionnaire analysis of 92.5% and the student response questionnaire of 90.3% in the very feasible category. The effectiveness of the e-module assisted by Augmented Reality is evidenced by an increase in pretest and posttest scores of 20.26, supported by a t-test result of 0.000, and an N-Gain score of 0.5314, which falls within the medium range. The research on the e-module assisted by Augmented Reality for the digestive system material was successfully developed, is very feasible, and is effective in improving the critical thinking skills of V-grade students at SDN Pendrikan Lor 03, Semarang City.
Copyright (c) 2026 Adinda Zulfa Kamila, Aldina Eka Andriani https://creativecommons.org/licenses/by/4.0
Development of Volta Drive Connect Media to Strengthen Energy Literacy of Elementary School Students
Science learning in elementary school often faces obstacles in conveying abstract concepts such as energy transformation, so it requires concrete learning media. This research aims to develop Volta Drive Connect, a project-based science teaching kit in the form of a solar-powered toy car, and to test its feasibility, practicality, and effectiveness in improving students' energy literacy. Using the Research and Development (R&D) method with the ADDIE model, this research was conducted with grade IV students at SD Nasional Kakuka and SD Negeri Simbarejo. The results of expert validation show that the design of the materials and media is highly feasible. In the effectiveness test, Volta Drive Connect proved to be significant in improving students' energy literacy. This was demonstrated by the paired-samples t-test (p<0.05), indicating an increase in the average score from 66.8 to 78.3. The use of this media not only motivates students and increases environmental awareness but is also aligned with the achievement of the Sustainable Development Goals (SDGs). In practice, this media provides an alternative innovative solution for teachers in facilitating student-centered basic science learning. In addition, the implementation of Volta Drive Connect encourages students to actively participate in learning through hands-on experimentation and collaborative activities. Students are involved in assembling and testing solar-powered toy cars, allowing them to understand the concept of energy transformation through real-world experiences. It also supports the development of science process skills, such as observation, problem-solving, and teamwork, which are important competencies in basic science education. Therefore, Volta Drive Connect not only contributes to improving students' conceptual understanding of energy but also to fostering positive attitudes towards renewable energy and sustainable environmental practices.
Copyright (c) 2026 Firnanda Millatin Afina, Ahmad Khoiri, Vava Imam Agus Faisal https://creativecommons.org/licenses/by/4.0
Implementation of Project-Based Simple Science Media in Science Learning: Strengthening Mutual Cooperation, Critical, and Creative Reasoning of Elementary School Students
Social studies learning in the Independent Curriculum requires a contextual, participatory, and oriented learning experience that strengthens the Pancasila Student Profile. However, learning practices in elementary schools still tend to be dominated by conventional approaches, so that students' active involvement in understanding science concepts and developing character is not optimal. This study aims to describe the implementation of project-based science media through Volta Drive Connect, analyze student responses, and strengthen the three-dimensional Pancasila Student Profile in science learning. This study used a descriptive qualitative approach with 18 grade IV students of Kakuka National Elementary School. Data was collected through observation, interviews, and documentation. Data analysis uses the interactive model of Miles, Huberman, and Saldana through the stages of data reduction, data presentation, and conclusion drawing and verification. The results showed that implementing Volta Drive Connect encouraged active student involvement throughout the learning process. Indicators of mutual cooperation are evident in the sharing of roles during collaborative assembly, discussion, retrying, and problem-solving activities. The indicators of mutual cooperation were evident in group cooperation (88.9%), role sharing (77.8%), and mutual help (83.3%). Critical reasoning indicators were seen through the ability to ask questions 66.7%, analyze problems 72.2%, and draw conclusions 61.1%. Meanwhile, creative indicators emerged in the ability to generate ideas (72.2%), try alternative solutions (83.3%), and modify the results of work (55.6%). The novelty of this research lies in the use of simple science media that connect the concept of energy to daily life and also show the strengthening of students' character that develops during the learning process. Thus, project-based simple science media can be an alternative to IPAS learning that is contextual and meaningful, and that supports the strengthening of the Pancasila Student Profile.
Copyright (c) 2026 Farah Nailis Saniyyah, Nasokah Nasokah, Ashief El-Qorny https://creativecommons.org/licenses/by/4.0
Development of a Student Worksheet Based on a Three-Dimensional Thinking Graph to Support Students’ Critical Thinking Skills
Chemical bonding is a fundamental topic in chemistry that is often considered abstract and difficult for students to understand, resulting in low critical thinking skills. The lack of interactive and technology-based teaching materials further exacerbates this problem. Therefore, this study aims to develop an electronic student worksheet based on the Three-Dimensional Thinking Graph on chemical bonding and determine its feasibility in supporting students' critical thinking skills. This study uses the Research and Development (R&D) method with the ADDIE model limited to the analysis, design, development, implementation, and evaluation stages. Data were collected through interviews, questionnaires, expert validation sheets, teacher assessments, and student responses. The product was validated by two validators, material and media experts, and one expert in learning design and Problem-Based Learning. The product trial involved 10 students from class XII F1B at SMAN 11 Muaro Jambi, conducted through one-to-one and small-group tests. Data analysis techniques used percentage analysis and qualitative descriptive analysis. The results showed that the electronic student worksheet obtained a validation score of 92% from material and media experts and 88.57% from learning design experts, with the category of very feasible. Teacher assessments reached 91% and student responses were 86%, categorized as very good. The novelty of this research lies in the integration of concept maps, data tables, and reasoning maps in an interactive electronic student worksheet based on TDTG to systematically support the development of students' critical thinking skills. Thus, the developed electronic student worksheet is deemed feasible and has the potential to support more interactive and meaningful learning of chemical bonds.
Copyright (c) 2026 Nia Diniati, Afrida Afrida, Asmiyunda Asmiyunda, Kriswantoro Kriswantoro, Febbry Romundza https://creativecommons.org/licenses/by/4.0
Analysis of Total Flavonoid Content in Local Kalimantan Plants and Antioxidant Activity: A Review
Flavonoids are one of the largest groups of compounds in the natural phenol group that are widely found in all types of green plants, so they are almost always found in every analysis of plant extracts. Meanwhile, antioxidants are inhibitors used to inhibit the autooxidation process. Flavonoids have the ability to act as antioxidants because they can transfer electrons, so they can neutralize free radicals. This review identifies the levels of flavonoids and antioxidant activity of local Kalimantan plants, utilizing half-maximal inhibitory concentration (IC50) values as a standardized quantitative parameter for assessing antioxidant potency and identifying promising sources of natural antioxidants. The maceration extraction method with ethanol at concentrations of 70% and 96% was used to obtain active compounds, and antioxidant activity was assessed using the DPPH method. The results showed that several species, such as Bajakah Kalalawit (Uncaria cordata) and Karamunting (Rhodomyrtus tomentosa), had very low IC50 values, namely 9.159 ppm and 14.06 μg/mL, indicating very strong antioxidant activity. Thus, local Kalimantan plants have great potential as a source of natural antioxidants and could be developed as raw materials for antioxidant-based health products. The findings of this review offer comprehensive evidence to guide future research, standardization, and commercialization of indigenous Kalimantan plants for the development of effective and sustainable natural antioxidant products.
Copyright (c) 2026 Nabilla Faoziyyah Azizah, Wildan Hidayah, Risa Dwi Apriani, Dia Septiani https://creativecommons.org/licenses/by/4.0
Development of a Critical Thinking Skills Test Instrument Based on Rasch Modelling for Temperature and Heat
Critical thinking skills are essential competencies in 21st-century physics learning. However, the availability of assessment instruments that accurately measure these skills remains limited, particularly for physics topics such as temperature and heat. Previous studies have rarely integrated Rasch modelling into the development of critical-thinking assessment instruments, particularly at the secondary school level. Therefore, this study aimed to develop and analyze the validity, reliability, and item fit of a critical thinking skills test instrument on temperature and heat topics using the Rasch model. This study employed a Research and Development (R&D) approach using the ADDIE model, comprising Analysis, Design, Development, Implementation, and Evaluation stages. The instrument consisted of 20 multiple-choice items constructed from critical-thinking indicators. Content validity was analyzed using Aiken’s V, while empirical analysis was conducted using the Rasch model through Ministeps Software. The analysis included item reliability, person reliability, item fit, difficulty level, and unidimensionality. The results showed that the instrument achieved an average Aiken’s V value of 0.8068, indicating that the instrument met the content validity criteria. Rasch analysis revealed that the item reliability was 0.86, while the person reliability was 0.35. In addition, 19 items were categorized as fit, whereas one item was identified as a misfit and required revision. The instrument also met the unidimensionality requirement with a raw variance explained value of 22.7%. In conclusion, the developed instrument meets the criteria for validity, reliability, and item fit and is suitable for measuring students’ critical thinking skills on topics related to temperature and heat. The findings indicate that Rasch modelling can support the development of more objective and comprehensive assessment instruments for physics learning and classroom assessment practices.
Copyright (c) 2026 Elmerita Dwi Agustin, Hera Novia, Raden Giovanni Ariantara https://creativecommons.org/licenses/by/4.0
Implementation of a PBL Model Based on a Process Differentiation Approach to Improve High School Students’ Problem-Solving Skills in the Topic of Static Fluids
Problem-solving skills are considered essential competencies in 21st-century physics education, yet many students experience difficulties in solving physics problems effectively. This study aimed to examine the effectiveness of applying a Problem-Based Learning (PBL) model integrated with a process differentiation approach in enhancing senior high school students’ problem-solving skills on the topic of static fluids. The study employed a quantitative quasi-experimental design with a nonequivalent control group format. Participants consisted of 68 eleventh-grade students from a public senior high school in Bandung, divided into an experimental group and a control group. In the experimental class, process differentiation was implemented through varied learning activities tailored to students’ learning-style characteristics. Data were gathered through essay-based tests designed to measure problem-solving skills and were analyzed using N-Gain and Mann–Whitney tests. The findings revealed that students in the experimental class showed greater improvement, with an average N-Gain score of 0.51, compared to 0.31 in the control class. In addition, the calculated Cohen’s d value of 1.1 indicated a strong practical effect of the treatment. The results suggest that integrating process differentiation into the PBL model effectively improves students’ problem-solving skills in learning about static fluids. The findings contribute to the growing body of evidence supporting the integration of differentiated instruction with Problem-Based Learning as an effective pedagogical approach for physics education.
Copyright (c) 2026 Karimah Fajriani, Lina Aviyanti, Winny Liliawati https://creativecommons.org/licenses/by/4.0
Phytochemical Screening and Total Flavonoid Content of the Combined Ethanol Extract of Turmeric (Curcuma longa) Rhizome and Ginseng (Panax ginseng) Root
Turmeric (Curcuma longa) and ginseng (Panax ginseng) are medicinal plants with high antioxidant potential due to their rich phytochemical constituents; however, the synergistic effect of their combined extraction has not been fully explored. This study aimed to identify the secondary metabolite profile and determine the total flavonoid content of the combined ethanolic extract of turmeric rhizome and ginseng root at a 1:1 ratio. Extraction was performed using the maceration method with 96% ethanol. Qualitative phytochemical screening was conducted to identify major secondary metabolites, while total flavonoid content was measured using the aluminium chloride (AlCl₃) colourimetric method by UV-Vis spectrophotometry at 415 nm with quercetin as the standard. All measurements were carried out in triplicate and analyzed using One-Way ANOVA followed by Tukey HSD post hoc test. The phytochemical screening showed positive results for flavonoids, saponins, tannins/phenolics, and triterpenoids. The combined extract exhibited a total flavonoid content of 48.65 ± 1.2 mg QE/g extract, which was significantly higher (p < 0.05) than the single turmeric extract (41.05 ± 0.9 mg QE/g) and the single ginseng extract (27.59 ± 0.7 mg QE/g). These findings indicate a synergistic interaction during co-maceration that enhanced flavonoid yield. In conclusion, the combined formulation improved the extraction efficiency of bioactive compounds and provides a scientific basis for the development of standardized phytopharmaceutical raw materials. Further in vivo studies are recommended to evaluate its therapeutic and neuroprotective potential.
Copyright (c) 2026 Anak Agung Istri Mas Padmiswari, Nadya Treesna Wulansari, Kadek Buja Harditya https://creativecommons.org/licenses/by/4.0
Comparative Effect of Acetic Acid and Bilimbi (Averrhoa bilimbi L.) Extract on the Extraction and Characteristics of Chicken Skin Gelatin
Chicken skin is a potential halal collagen source for gelatin production, especially as an alternative to bovine and porcine gelatin. This study aimed to compare acetic acid and bilimbi fruit extract (Averrhoa bilimbi L.) as acid pretreatment agents for extracting gelatin from chicken skin. The novelty of this study lies in comparing a common food-grade acid with a local natural acid source for sustainable halal gelatin production from poultry by-products. Chicken skin was pretreated with 0.15% NaOH, soaked in acetic acid or bilimbi extract at 2%, 3%, and 4% (m/v) for 24 h, extracted at 65°C for 90 min, and dried at 55°C for 24 h. The gelatin was analyzed for yield, moisture content, ash content, pH, and Fourier Transform Infrared (FTIR) spectra. Data were presented as mean ± standard deviation and analyzed using two-way ANOVA followed by Tukey’s HSD test at p < 0.05. The results showed that gelatin yield ranged from 2.35 ± 0.04% to 10.65 ± 0.07%. Acetic acid produced higher yield than bilimbi extract at the same concentration. The best treatment was 4% acetic acid, which produced the highest yield (10.65 ± 0.07%), low moisture content (9.42 ± 0.08%), low ash content (1.48 ± 0.04%), and pH of 4.48 ± 0.02. FTIR analysis showed amide A, amide B, amide II, and amide III bands, indicating partial hydrolysis of collagen into gelatin. Although bilimbi extract showed lower extraction efficiency, it still has potential as a sustainable local acid source for halal gelatin extraction. These findings support the utilization of chicken skin and local natural resources for sustainable halal gelatin production.
Copyright (c) 2026 Mifta Hurahmi, Edi Saputra, Miftahul Khair https://creativecommons.org/licenses/by/4.0
Development of Augmented Reality-Based Flashcard Learning Media on Human Respiratory System Materials
Teachers have not been optimal in developing technology-based learning media in the form of interactive games, so that student learning outcomes on human respiratory system materials in elementary schools are still low. This study aims to describe the design, feasibility, and effectiveness of Augmented Reality-based flashcards for improving the learning outcomes of grade V students on the human respiratory system. This research is a Research and Development (R&D) with the ADDIE model, which includes the stages of analysis, design, development, implementation, and evaluation. The research subjects amounted to 27 students in class V. Data collection techniques included observation, interviews, questionnaires, documentation, and pretest and posttest assessments. Data were analyzed using normality tests, Paired Sample t-Test, and N-Gain tests. The flashcard media was developed using Canva and integrated with AR technology through the Assemblr Edu platform to support concrete and interactive visualization of concepts. Integrating AR-based flashcards into interactive edugames for elementary students. This Augmented Reality contains explanations of respiratory organs, organ functions, interesting facts, respiratory organ disorders, and human breathing mechanisms. The validation results showed that the media was highly feasible to use, with validation by material experts at 91.07% and by media experts at 95.37%. The responses of teachers and students also showed very positive results with percentages of 96.59% and 90%, respectively. The effectiveness of the media was demonstrated by an increase in the average score from 55.25 on the pretest to 74.25 on the posttest, with a Sig. p-value of < 0.001 and an N-Gain score of 0.4581 in the medium category. The findings of the study show that AR-based flashcards have been successfully developed, are highly feasible, and are effective in improving student learning outcomes, serving as an innovative learning medium that supports engaging and interactive science learning.
Copyright (c) 2026 Meytania Najwa Putri Azzahra, Aldina Eka Andriani https://creativecommons.org/licenses/by/4.0
Analysis of Metabolite Profile of Gambier Flower (Uncaria gambir (Hunter) Roxb.) in Various Solvent Fractions Using LC-MS
The gambier plant is known as a rich source of secondary metabolites with biological activities, including anticancer, antioxidant, and antimicrobial properties. The leaves of the gambier plant are reported to contain flavonoids, including catechins, and tannins. This study aims to analyze the metabolite profile of gambier flowers using Liquid Chromatography-Mass Spectrometry (LC-MS). Gambier flower samples were extracted by maceration using ethanol as the solvent. The resulting macerate was then fractionated using n-hexane, ethyl acetate, and n-butanol. The gambier flower extracts were tested for phytochemical content via thin-layer chromatography (TLC) and analyzed for secondary metabolite content via LC-MS for each fraction. TLC testing of the total extract yielded positive results for flavonoids, steroids, phenolics, and alkaloids. Analysis of the secondary metabolite profile of the total extract identified 6 compounds from the 14 compound chromatograms that appeared; the n-hexane extract showed 6 compounds successfully identified from a total of 20 compounds, the ethyl acetate extract showed 6 identified compounds from 17 compounds, and the n-butanol extract contained 7 known compounds from 35 compounds. From the metabolite profile analysis, it can be concluded that gambier flowers contain numerous bioactive compounds with potential for further development and can serve as a source of new knowledge in exploring plant potential. To the best of our knowledge, this is the first LC-MS-based metabolite profile of gambier flowers, an organ that has remained largely unexplored compared with the widely studied leaves; the flowers display a greater diversity of flavonoid glycosides and phenolic derivatives, highlighting their novelty and their promise as antioxidant-rich raw materials for the pharmaceutical and cosmetic industries.
Copyright (c) 2026 Arif Ferdian, Amri Bakhtiar, Suci Salwa Fitri Mustafa, Neny Sandrawati https://creativecommons.org/licenses/by/4.0
Food Safety Assessment of Wet Noodles: Detection of Methanyl Yellow in Kebon Roek Traditional Market, Mataram City
Wet noodles are one of the most commonly consumed food products in Indonesia and are often used as an alternative staple food to rice. To enhance product appearance, some producers may add coloring agents to wet noodles. One of the prohibited synthetic dyes is Metanil Yellow, which can cause various health problems, including respiratory irritation, skin irritation, eye irritation, and an increased risk of cancer when consumed continuously over a long period. This study aimed to determine the presence of Metanil Yellow in wet noodles sold at Kebon Roek Market in Ampenan, Mataram City, in 2025. This study employed a descriptive qualitative research design. Samples were selected using purposive sampling based on the physical characteristics of wet noodles suspected to contain Metanil Yellow. A total of five wet noodle samples were analyzed qualitatively using the wool yarn method at the Environmental Health Laboratory of the Mataram School of Environmental Engineering (STTL Mataram). A positive result for Metanil Yellow was indicated by a purple-reddish color change in the wool yarn after the addition of 37% hydrochloric acid (HCl). The results showed that none of the tested samples exhibited a color change in the wool yarn after testing, indicating that all samples were negative for Metanil Yellow. These findings suggest that the wet noodles sold at Kebon Roek Market, Ampenan, Mataram City, during the study period complied with food safety standards prohibiting synthetic dyes in food products.
Copyright (c) 2026 Dini Yuliansari, Nurhidayatullah Nurhidayatullah, Renaldi Renaldi https://creativecommons.org/licenses/by/4.0
Design and Development of a Wastewater Treatment Plant System for Improved Ammonia Removal at Metro Medika Hospital
Hospital wastewater contains various pollutants, including ammonia, which may contaminate receiving water bodies and threaten environmental health if not adequately treated. The existing wastewater treatment plant (WWTP) at Metro Medika Hospital, Mataram, was unable to consistently reduce ammonia concentrations to comply with the regulatory limit of 10 mg/L, with the latest effluent concentration reaching 58.1 mg/L. Therefore, this study aimed to redesign the hospital WWTP to improve ammonia removal through the optimization of an integrated anaerobic-aerobic biological treatment system. A laboratory-scale experimental study was conducted using actual hospital wastewater in a modified treatment system consisting of anaerobic and aerobic biofilters, a bioball reactor, and a disinfection unit. The novelty of this study lies in integrating sequential anaerobic-aerobic biological treatment with a combination of attached-growth biofilter media, including DD-01 media, honeycomb media, bioballs, gravel, silica sand, zeolite, and plastic media, to enhance nitrification performance while maintaining a simple and practical treatment configuration. Data were analyzed using descriptive analysis by comparing influent and effluent ammonia concentrations, while treatment performance was evaluated through ammonia removal efficiency calculations. The redesigned WWTP reduced ammonia concentration from 58.1 mg/L to 10.0 mg/L, corresponding to an ammonia removal efficiency of 82.77%, thereby meeting the applicable wastewater quality standard. These findings demonstrate that the proposed WWTP design offers a feasible approach for improving ammonia removal and a promising strategy to support sustainable hospital wastewater management and regulatory compliance.
Copyright (c) 2026 Hairun Anwar, Taufik Abdullah, Azwaruddin Azwaruddin, Hismi Susane https://creativecommons.org/licenses/by/4.0
Water Quality Assessment of the Ancar River, Lombok Island
River water quality is a parameter to determine whether the river is polluted or not. The purpose of this study is to analyze the water quality of the Ancar River located on Lombok Island, West Nusa Tenggara, based on seven main parameters, namely temperature, pH, TSS, DO, BOD, COD, and total coliform. The study employed a descriptive-qualitative approach and evaluated water quality status using the Pollution Index method, in accordance with the Decree of the Minister of Environment No. 115 of 2003. Sampling was carried out at three strategic points representing the upstream, middle, and downstream zones of the river. The data collection method used a grab sampling technique in accordance with SNI 03-7016-2004, and laboratory analysis was conducted at STTL Mataram. The test results were compared with the river water quality standards for classes I to IV under PP No. 22 of 2021. The results showed that most water quality parameters in the Ancar River remained within the quality standard thresholds, particularly temperature, pH, TSS, DO, and total coliform. However, COD values ​​at all observation points exceeded the limits for classes I–III and only met class IV, while BOD increased from upstream to downstream. These results indicate the presence of organic pollution, primarily from domestic activities and household waste, necessitating more optimal water quality management.
Copyright (c) 2026 Imam Mauliddin, Tina Melinda, Muhamad Majdi https://creativecommons.org/licenses/by/4.0
Environmental Monitoring of Water Quality in the Jangkok River, Mataram City
The increase in population and domestic activities of the community along the banks of the Jangkok River contribute to the decline in river water quality. This study aims to analyze the water quality of the Jangkok River based on physical and biological parameters by comparing the measurement results to class III water quality standards according to PP No. 22 of 2021 and evaluate the water quality status using the Pollution Index according to the Decree of the Minister of Environment No. 115 of 2003. This type of research is Descriptive Quantitative. Sampling was conducted at three points upstream, downstream, and midstream and the samples were tested in the laboratory using Indonesian National Standard methods. The results show that the temperature in the upstream, middle and downstream sections is 26.3oC, the highest TSS value is in the upstream section, namely TSS 0.119 mg/L, the highest pH value is in the downstream section, namely 6.07, the highest DO value is in the upstream section, namely 19.78 mg/L, the highest BOD value is in the middle section, namely 4.48 mg/L, the highest COD value is in the downstream section, namely 84 mg/L and the lowest total coliform is in the upstream section, namely 91 MPN/ml. Several parameters, such as pH, DO, and COD, do not meet the class III quality standards under PP No. 22 of 2021, while temperature, TSS, BOD, and total coliform remain below these standards. The Pollution Index at all points is in the "lightly polluted" category, with IP values of 3.69 upstream, 3.68 in the middle, and 3.30 downstream. Domestic waste activities along the Jangkok River significantly impact water quality, although overall pollution levels remain relatively low. Waste management and public education are needed to maintain the river's sustainable function.
Copyright (c) 2026 Muhammad Mardian Rizaldi, Tina Melinda https://creativecommons.org/licenses/by/4.0
Synthesis and Characterization of ZnO/CaO Nanocatalysts and Utilization in Biodiesel Transesterification Reaction from Waste Cooking Oil
The increase in global energy demand has led to increased consumption of fossil fuels, resulting in increasingly depleted energy reserves. In addition, the use of fossil fuels has various negative environmental impacts, including air pollution, global warming, and greenhouse gas emissions. Therefore, the development of environmentally friendly, sustainable alternative energy sources is needed. One renewable energy source with development potential is biodiesel. This study aims to synthesize biodiesel from waste cooking oil through a transesterification reaction using ZnO/CaO nanocatalysts. The novelty of this research lies in the synthesis of ZnO/CaO nanocatalysts via a combination of sol-gel and impregnation methods, which are expected to increase the catalysts' surface area, stability, and catalytic activity. The CaO catalyst was synthesized using the sol-gel method and modified with ZnO through a wet impregnation method using Zn acetate precursor at various concentrations of 0%, 1%, 2%, and 3%. FTIR and XRD characterizations confirmed the success of ZnO impregnation on CaO, while PSA analysis showed a decrease in particle size from 107.85 nm on CaO to 79.28 nm on 1% ZnO/CaO, which has the potential to increase catalytic activity. The transesterification reaction was carried out at 65°C for 2 hours, using a methanol-to-oil molar ratio of 1:9 and a catalyst loading of 3% of the oil weight. The resulting biodiesel was then analyzed using GC-MS, and it was found that ZnO modification increased the methyl ester area percentage from 92.74% in CaO to 99.61% in ZnO/CaO 1%. In addition, the highest biodiesel yield using 1% ZnO/CaO produced a density of 853.8 kg/m³, a viscosity of 2.30 mm²/s (cSt), a water content of 0.02%, and an acid number of 0.43 mg-KOH/g.
Copyright (c) 2026 Neristia Viky Marta, Amalia Putri Purnamasari https://creativecommons.org/licenses/by/4.0
Development of Multiple-Choice Based on Automatic Assessment through Quizizz Respiratory System Material in Humans
Teachers have not been effective in presenting learning evaluations, using a variety of stimuli and question types, resulting in delays in delivering feedback to students. This study aims to describe the development design, test the feasibility, and test the effectiveness of multiple-choice questions based on automatic assessment via Quizizz, using respiratory system material in class V SD N Sekaran 01, Semarang City. The research conducted is R&D (Research and Development) and the ADDIE (analysis, design, development, implementation, Evaluation) development model. The data collection technique uses both tests and non-tests. Data analysis techniques included normality testing, t-tests, and N-Gain. The results of this study include the design of a multiple-choice development based on automatic assessment through Quizizz, with the following question types: standard multiple choice, complex multiple choice, and two-tier multiple choice. Each question is accompanied by a varied, context-specific stimulus in the form of videos, images, tables, and narrative text. The feasibility of multiple-choice automatic assessment via a questionnaire on respiratory system material in humans was demonstrated, with material experts achieving 92.85% and media experts achieving 89.28%, both within very feasible criteria. The effectiveness of multiple-choice questions based on automatic assessment through Quizizz showed an increase in pre-test and post-test by 28.08. The Paired Sample t-test yielded a p-value of 0.00, indicating a significant difference in student learning outcomes, which is supported by the N-Gain test, which yielded 0.5687 with moderate criteria. Thus, a multiple-choice assessment based on Automatic Assessment through Quizizz has been successfully developed, is feasible, and effective in improving students' learning outcomes in grade V at SD N Sekaran 01, Semarang City.
Copyright (c) 2026 Lavina Azza Khaerina, Aldina Eka Andriani https://creativecommons.org/licenses/by/4.0
Effect of the Self-Regulated Learning Model on High School Students’ Physics Problem-Solving Ability
Physics education within the Kurikulum Merdeka emphasizes the development of students' problem-solving ability as an essential competency for addressing twenty-first-century challenges. However, physics teaching practices in many Indonesian schools continue to rely heavily on teacher-centered instructional approaches, limiting students' opportunities to develop systematic problem-solving ability. This study aimed to examine the effect of the Self-Regulated Learning (SRL) model on senior high school students' physics problem-solving ability. A quasi-experimental study employing a nonequivalent control group pretest–posttest design was conducted with 64 tenth-grade students at SMA Negeri 3 Singaraja, Indonesia. Students' problem-solving ability was measured using a validated essay test, and the data were analyzed using one-way Analysis of Covariance (ANCOVA) with pretest scores as covariates. Prior to the intervention, the SRL and conventional groups demonstrated comparable mean pretest scores of 36.67 (SD = 5.40) and 35.83 (SD = 4.81). After the intervention, students in the SRL group achieved a higher mean posttest score of 73.33 (SD = 5.32) than those in the conventional group, 69.17 (SD = 5.14). ANCOVA revealed a statistically significant effect of the learning model on students' problem-solving ability (F = 17.067, p < 0.001), with a large practical effect (partial η² = 0.219). Furthermore, the estimated marginal mean difference between the two groups was 5.095 points (95% CI [2.498, 7.691]), indicating a consistent advantage of the SRL model over conventional instruction. These findings demonstrate that SRL is substantially more effective in enhancing students' ability to understand problems, formulate solution strategies, implement appropriate procedures, and evaluate solutions. Therefore, the SRL model represents an effective student-centered instructional approach for strengthening physics problem-solving ability and supporting the implementation of the Kurikulum Merdeka.
Copyright (c) 2026 I Gede Septa Gangga Merta, Putu Yasa, Putu Widiarini https://creativecommons.org/licenses/by/4.0
Integrating Artificial Intelligence into Problem-Based Learning to Enhance Self-Regulated Learning
Technological advancements in the digital age have brought significant changes to the learning process; however, students’ self-regulated learning skills in science education still need to be improved, particularly in their ability to plan, monitor, and evaluate the learning process. Therefore, technology-based learning innovations such as Artificial Intelligence (AI) are needed to provide rapid and personalized feedback to support Self-Regulated Learning (SRL). This study aims to determine the effect of integrating Artificial Intelligence (AI) into the Problem-Based Learning (PBL) model on students’ Self-Regulated Learning (SRL) skills in science education. This study employs a quantitative approach with a one-group experimental design, involving 17 students in the experimental class and 10 students in the replication class, selected through purposive sampling. The research instrument consists of a Self-Regulated Learning questionnaire. Data analysis was conducted using descriptive statistics, the Shapiro-Wilk normality test, and a one-sample t-test for hypothesis testing. The results showed that the mean Self-Regulated Learning (SRL) scores of students in the experimental class were 90.12 and 92.40 in the replication class, both falling into the high category, and the data were normally distributed with significance values of 0.842 and 0.589, respectively (p > 0.05). The results of the hypothesis test showed a p-value of 0.000 for the experimental class.
Copyright (c) 2026 Nurinda R. Bakri, Abdul Haris Odja, Dewi Diana Paramata, Citron S. Payu, Mursalin Mursalin https://creativecommons.org/licenses/by/4.0
Effect of the Amount of Phenoxyethanol as a Preservative in Cosmetic Preparations on the Incidence of Skin Irritating Side Effects: A Review
Phenoxyethanol is one of the most widely used preservatives in the cosmetics industry, commonly found in moisturizers, lotions, facial cleansers, and baby care products. Despite its widespread use, published studies have reported inconsistent findings on its irritant potential across product types and concentration ranges, and no comprehensive review has systematically compared phenoxyethanol irritation outcomes across multiple cosmetic formulations and testing methods. This study aims to analyze the irritation potential of phenoxyethanol as a preservative in various cosmetic formulations through a systematic review approach. This study employed a systematic literature review following PRISMA guidelines. Data synthesis was conducted using qualitative comparative analysis to systematically compare irritation test outcomes across phenoxyethanol concentration ranges, cosmetic product types, and irritation testing methods (in vivo and in vitro). Findings were grouped into three concentration categories. In the low-concentration group (0.1%–<0.5%), all formulations showed excellent safety profiles, including a face mist containing 0.2% phenoxyethanol with vitamin E and a body scrub cream containing 0.1% phenoxyethanol with DMDM hydantoin, both of which showed no significant irritation in in vivo tests. In the medium concentration group (0.5%–1%), all formulations, including moisturizing gel, body lotion, deodorant stick, blush on cream, hair tonic, and sunscreen lotion, consistently showed no significant irritation across in vivo human panelist tests, animal models, and in vitro HET-CAM testing. In contrast, the high concentration group (>1%), represented by a coffee grounds body scrub cream at 1.5%–1.6%, showed increased irritation. These findings confirm that phenoxyethanol at concentrations of 0.1%–1% is safe and does not cause significant irritation across various cosmetic preparations, supporting the 1% maximum limit established by BPOM Regulation Number 25 of 2025. Exceeding this limit increases the risk of irritation, particularly for individuals with sensitive skin.
Copyright (c) 2026 Ailla Az-zahraa, Devi Ratnasari, Diva Valentin, Theresia Natalie Cahyani, Tasya Permata Shella, Muhammad Adit Adzkia, Nariyyah Fitriana https://creativecommons.org/licenses/by/4.0
Developing a Science Process Skills Assessment on Cell and Microscope: A Rasch Analysis
Science process skills (SPS) are essential competencies in science education; however, various studies indicate that students’ SPS achievement remains relatively low. Furthermore, existing assessment instruments do not fully align with the learning outcome indicators. This study aims to develop a valid and reliable SPS test instrument for cell and microscope topics through Rasch model analysis. The research method employs a Research and Development (R&D) approach using the ADDIE model, which includes the Analyze, Design, Develop, Implement, and Evaluate stages. The developed instrument consists of 25 multiple-choice items covering 6 SPS indicators: observing, questioning and predicting, planning and conducting investigations, processing and analyzing data, evaluating and reflecting, and communicating results. Content validation was conducted by 5 validators, yielding an average Aiken’s V of 1.00, indicating excellent alignment between the items and the measured indicators. Rasch analysis using the Winsteps applications showed that all items met the fit criteria based on outfit MNSQ values, with difficulty levels ranging from very easy to very difficult. The instrument demonstrated high reliability (α = 0.97) and adequate item separation, indicating strong consistency and discriminative power. Implementation involving 32 seventh-grade students revealed that most students were categorized as having moderate SPS level, suggesting that their SPS had developed but was not yet optimal across all indicators. These results confirm the instrument's validity and reliability in assessing junior high school students’ SPS. This study contributes a Rasch-based assessment instrument that can objectively map students’ SPS abilities and support the evaluation of science learning.
Copyright (c) 2026 Della Pusvita Anggraeni, Risa Dwita Hardianti https://creativecommons.org/licenses/by/4.0
Exploring the Potential of Depati VII Coffee and Resort as a Bio-Edutourism Site in High School Biology Education: A Phenomenological Study
This phenomenological qualitative study explores the use of Depati VII Coffee & Resort as a bio-edutourism destination for high school students, with the aim of addressing the gap in utilizing local ecological and cultural potential, a gap that often results in abstract biology instruction. Bordering Kerinci Seblat National Park, this site offers a rich highland coffee agroecosystem. Data were collected over three months through in-depth interviews, participatory observation, and documentation, then analyzed through the stages of data condensation, horizontalization of significant statements, thematic grouping, and textural-structural description. The research successfully synthesized a Three-Subsystem Bio-Edutourism Framework in which the subsystems are mutually integrated. First, the Ecological Subsystem serves as a natural laboratory with a mountain microclimate, multistrata agroforestry, and biodiversity, facilitating understanding of biological concepts. Second, the Ethnopedagogical Subsystem utilizes traditional architecture (Rumah Basilo), local technologies (jangki, lukah), and Kerinci moral proverbs such as “nature is entrusted to us, not to be destroyed” to foster character and an environmentally conscious attitude. Third, the Pedagogical Subsystem organizes field-based learning strategies grounded in Kolb’s experiential learning theory and inquiry-based worksheets. On the other hand, this study reveals real challenges, such as students' divided focus between recreation and learning, time constraints, and the need for structured observation guidelines to prevent the activities from becoming ordinary sightseeing. Overall, this three-subsystem model makes a significant theoretical and practical contribution to strengthening science literacy, environmental awareness, and local cultural identity in a sustainable manner.
Copyright (c) 2026 Rodiantifitri Nengsih, Nosi Qadariah, Sri Yuni Hastutin https://creativecommons.org/licenses/by/4.0
Green Synthesis of Zinc Oxide Nanoparticles (ZnONPs) Using Illicium verum Flower Extract as a Bioreductor and Its Antibacterial Activity Against Escherichia coli
Zinc oxide nanoparticles (ZnONPs) have attracted considerable attention as antibacterial agents due to their superior physicochemical properties. This study aimed to synthesize ZnONPs via a green synthesis approach using Illicium verum flower extract, which is rich in phytochemical compounds, as a natural bioreductant, as well as to determine the optimal synthesis conditions and characterize the resulting nanoparticles. The synthesis was carried out using zinc acetate dihydrate, with variations in the precursor-to-extract volume ratio (1:1–1:4) and pH (7–11). Characterization was performed using UV–Vis spectrophotometry, Fourier Transform Infrared Spectroscopy (FTIR), and Particle Size Analysis (PSA), while antibacterial activity against Escherichia coli was evaluated using the disk diffusion method. The results showed that the optimal conditions were achieved at a volume ratio of 1:2 and a pH of 10, with a maximum absorption wavelength of 385 nm. The synthesized ZnONPs exhibited an average particle size of 18.27 nm with a low polydispersity index (0.1769), and the presence of Zn–O functional groups was confirmed by FTIR analysis. Furthermore, ZnONPs demonstrated very strong antibacterial activity against Escherichia coli, with an inhibition zone diameter of 32.49 mm, which was higher than that of the Illicium verum extract. These findings indicate that Illicium verum extract is an effective natural bioreductant for the green synthesis of ZnONPs and highlight the potential of the synthesized nanoparticles as efficient and environmentally friendly antibacterial agents. This study also demonstrates the feasibility of utilizing Illicium verum flower extract for ZnONP synthesis and antibacterial applications against Escherichia coli.
Copyright (c) 2026 Bagus Ramadhani, Suyatno Sutoyo, Radita Yuniar Arizandy, Wahyu Setyarini https://creativecommons.org/licenses/by/4.0
Development of Multimedia Based on Problem Based Learning to Improve Learning Outcomes in Energy Transformation
Teachers have not optimally used technology-based learning media, such as interactive edugames, resulting in poor student learning outcomes on the topic of energy transformation. This study aims to describe the development and design, and to test the feasibility and effectiveness of multimedia-based problem-based learning (PBL) to improve fourth-grade students' learning outcomes on the topic of energy transformation at SDN Tambakaji 03, Semarang City. This research used the Research and Development (R&D) method with the ADDIE model. The subjects were 28 fourth-grade students at SDN Tambakaji 03, Semarang City. Data collection techniques included non-test methods (observations, interviews, questionnaires, and documentation) and test methods (pretests and posttests). Data analysis techniques used included a normality test, a paired-samples t-test, and an N-Gain test. The results showed that the Multimedia, based on Problem-Based Learning for the topic of energy transformation, was designed in Canva and further developed in Genially. The feasibility results showed a content expert score of 95% and a media expert score of 96%, both categorized as “highly feasible,” supported by teacher response questionnaire results of 97.5% and student response questionnaire results of 97%, both also categorized as “highly feasible.” The effectiveness of the multimedia was indicated by an increase in pretest and posttest scores from 72.7 to 83.6, supported by a paired-samples t-test (p = 0.000 < 0.05) and an N-Gain score of 0.4439 (moderate criterion). The study concludes that multimedia-based problem-based learning was successfully developed, highly feasible, and effective in improving fourth-grade students' learning outcomes on energy transformation at SDN Tambakaji 03, Semarang City. This study is still limited to the essential concepts of energy transformation.
Copyright (c) 2026 Yasmin Atsara Ghumaisha, Aldina Eka Andriani https://creativecommons.org/licenses/by/4.0
Diversity of Dragonflies (Odonata) Anisoptera and Damselflies in the Kenjeran Fish Ponds, North Surabaya
Dragonflies (Odonata) are important bioindicators of aquatic ecosystem quality because their diversity and abundance are closely associated with environmental conditions and habitat stability. This study aims to determine the diversity of dragonflies of the order Odonata, suborder Zygoptera, in the Tambak Kenjeran area of North Surabaya. The research methods used were qualitative and quantitative, employing the time-search technique at two observation stations for one hour each, with three repetitions at the same time but on different days. Sampling was conducted with an insect net, and specimens were identified by morphological characteristics. The results showed that 86 dragonfly individuals were found, comprising two species: Ischnura senegalensis (Coenagrionidae) and Orthetrum sabina (Libellulidae). At Station 1, 46 individuals were found; at Station 2, 40. The most dominant species was Ischnura senegalensis with a total of 69 individuals, while Orthetrum sabina was found in 17 individuals. The diversity index values at Station 1 and Station 2 were 0.387212 and 0.588169, respectively, both classified as low. Low diversity index values indicate ecological stress and unstable ecosystem conditions in the pond area. This study is expected to provide information on dragonfly diversity and support efforts to conserve aquatic ecosystems in the Kenjeran Pond area. This confirms that the aquatic ecosystem in Kenjeran Pond is currently under stress and therefore requires serious attention in its management.
Copyright (c) 2026 Icha Alfiati, Ransha Diva Nabiilah https://creativecommons.org/licenses/by/4.0
Analysis of STEAM PBL-Based E-Worksheet to Improve Critical Thinking Skills
The 21st-century learning paradigm emphasizes critical thinking and problem-solving skills as essential competencies that must be developed to equip students to address increasingly complex global challenges and demands. Therefore, learning in schools should be designed to be innovative and contextual. This study aimed to evaluate the validity, practicality, and effectiveness of a problem-based learning e-worksheet incorporating the STEAM approach to enhance critical thinking skills in biology at State Senior High School 11 Palembang. The research model used the 4D development model, consisting of define, design, develop, and disseminate. The analysis techniques used include the Wilcoxon test, the Mann-Whitney test, and the N-gain analysis. Data collection techniques were interviews, questionnaires, and observations. The research population was students of grades X.2 and X.5. The analysis of the define stage showed that teachers and students need an e-worksheet based on the PBL model with the STEAM approach. The design stage included designing an e-worksheet. In the develop stage, the feasibility of the developed teaching materials was assessed at 90% from the aspects of language, materials, media, learning tools, and evaluation, so that it was categorized as very good. The practicality of the teaching tools was categorized as practical by teachers, with a percentage of 91.25% and the teaching materials could be read very well by students, with a percentage of 81%. The effectiveness of the e-worksheet based on the PBL model with the STEAM approach showed that the N-gain value for the control class was 0.33 (low criteria), while the experimental class was 0.78 (high criteria). In conclusion, an e-worksheet based on the PBL model with the STEAM approach can improve students' critical thinking skills.
Copyright (c) 2026 Rizma Melisa Bonet, Astrid Sri Wahyuni Sumah, Wulandari Saputri https://creativecommons.org/licenses/by/4.0
Association Between Household Drinking Water Access and Management Factors and Diarrhea in East Kalimantan Province: Analysis Of SKAMRT 2024 Data
Diarrheal disease remains a significant public health concern and is closely associated with access to drinking water and household drinking water management practices. According to the 2023 Indonesian Health Survey (SKI), the reported prevalence of diarrhea was 4.3% nationally and 4.2% in East Kalimantan Province. This study aimed to examine the association between household drinking water access and management factors and diarrhea in East Kalimantan Province using data from the 2024 Household Drinking Water Quality Surveillance (SKAMRT). A cross-sectional study was conducted using secondary data from 2,051 households. The main independent variables were drinking water source, drinking water continuity, household drinking water treatment, and drinking water storage. Education of the household head, household size, and place of residence were included as covariates. Data were analyzed using descriptive statistics, bivariate analyses with the chi-square test, and multivariable logistic regression. The prevalence of reported diarrhea was 4.5%. After adjustment for the other variables included in the model, intermittent drinking water access was significantly associated with higher odds of diarrhea (AOR = 6.10; 95% CI: 3.21–11.57; p < 0.001). Unsafe drinking water storage was also significantly associated with higher odds of diarrhea (AOR = 2.67; 95% CI: 1.38–5.19; p = 0.004). Drinking water source and household drinking water treatment were not significantly associated with diarrhea. These findings highlight the importance of improving the reliability of the drinking water supply and strengthening household education on safe drinking water storage. These findings should be interpreted cautiously because of the cross-sectional design and reliance on household-reported diarrhea.
Copyright (c) 2026 Akhmad Riyadi, Bambang Wispriyono https://creativecommons.org/licenses/by/4.0
Comparison of Biology Academic Achievement and Social Skills Between Yangon and Pyin Oo Lwin High School
Project-Based Learning (PBL) is increasingly recognized as an effective approach for enhancing both students’ academic achievement and social skills. This study examines differences in academic achievement in biology and social skills among high school students in Yangon and Pyin Oo Lwin, Myanmar. Yangon school implemented Project-Based Learning (PBL), whereas the Pyin Oo Lwin school employed traditional teaching methods. A descriptive comparative design was adopted, involving 120 Grade 10 students, with 60 selected from Yangon and 60 from Pyin Oo Lwin. Academic achievement was measured using monthly biology test scores, while social skills were assessed via a researcher-developed questionnaire covering five indicators: positive interdependence, interaction activity, individual responsibility, interpersonal relationships, and group member interactions. An independent samples t-test revealed significantly higher biology scores in Yangon (M = 75.80, SD = 5.97) than in Pyin Oo Lwin (M = 68.10, SD = 6.21; t = 7.01, df = 118, p < 0.01). A Mann–Whitney U test indicated significantly stronger collaboration scores in Yangon (93.5%, SD = 1.60) compared to Pyin Oo Lwin (91.7%, SD = 1.70; U = 577.00, p < 0.05). A Pearson correlation analysis showed a statistically significant, moderate positive relationship between academic achievement and social skills (r = 0.47, p < 0.001, r² = 0.22), indicating that the two variables share only about 22% of common variance. Given the descriptive comparative design, these findings indicate that PBL implementation is associated with higher academic achievement and stronger social skills among Yangon students, rather than directly causing these outcomes. The results underscore the need for equitable access to active learning methodologies across Myanmar's diverse regional contexts.
Copyright (c) 2026 Kaung Pye Hlyan, Imam Bachtiar, A. Wahab Jufri, Marosa Robiatul Adawiyah https://creativecommons.org/licenses/by/4.0
Effect of Giving Ethanol Extract of Keji Beling (Strobilanthes crispa L. Blume) Leaves on Histology and Liver Physiology in White Rats (Rattus norvegicus L.) Induced by Sodium Benzoate
Sodium benzoate is one of the most widely used food preservatives in the food and beverage industry due to its effectiveness in inhibiting microbial growth. However, excessive and prolonged consumption of sodium benzoate may induce adverse health effects, including gastrointestinal disturbances, neurological disorders, and liver damage resulting from oxidative stress. Natural medicinal plants with antioxidant properties have attracted considerable attention as potential therapeutic agents against chemical-induced organ toxicity. Keji Beling leaves (Strobilanthes crispa L. Blume) are traditionally utilized in Indonesia for various medicinal purposes and are known to contain bioactive compounds such as flavonoids, polyphenols, tannins, and saponins that exhibit hepatoprotective activity. This study aimed to evaluate the effect of ethanol extract of keji beling leaves on liver histology and liver physiological function, as indicated by serum glutamate pyruvate transaminase (SGPT) and serum glutamate oxaloacetate transaminase (SGOT) levels, in sodium benzoate-induced white rats (Rattus norvegicus L.). The experiment employed a Completely Randomised Design with five treatment groups at different extract dosages. Data were analyzed using one-way analysis of variance (ANOVA), followed by Duncan’s Multiple Range Test at a 95% confidence level. The results demonstrated that sodium benzoate administration significantly induced liver histopathological alterations characterized by cellular degeneration, inflammation, and necrosis, accompanied by elevated SGPT and SGOT levels. Treatment with the ethanol extract of keji beling leaves significantly improved liver histology and reduced liver enzyme levels compared with the sodium benzoate-induced group. The hepatoprotective effect was dose-dependent, with the dose of 500 mg/kg body weight showing the most effective recovery of liver tissue and normalization of SGPT and SGOT levels. These findings suggest that the ethanol extract of Strobilanthes crispa leaves has promising potential as a natural hepatoprotective agent against sodium benzoate-induced liver injury.
Copyright (c) 2026 Rizky Ayu Wulan Dari, Husnarika Febriani, Syukriah Syukriah https://creativecommons.org/licenses/by/4.0
Effect of the Problem-Based Learning Model on Problem-Solving Ability in the Materials of Matter and Its Changes
Problem-solving ability is a crucial competency in science learning that still requires improvement, particularly in the topic of matter and its changes. The low level of this skill highlights the need for more innovative and student-centered instructional approaches. This study aims to examine the effect of the Problem-Based Learning (PBL) model on students’ problem-solving abilities. This study aims to analyze the effect of the Problem-Based Learning (PBL) model on students’ problem-solving abilities in the topic of Matter and Its Changes at SMP Negeri 1 Silaen. The background of this research is the low level of students’ problem-solving skills due to the dominance of conventional, teacher-centered learning, which causes students to be passive and less trained in developing problem-solving strategies. This research uses a quantitative approach with a quasi-experimental design of the non-equivalent control group type. The sample was selected using purposive sampling, with Class VII-D (26 students) as the experimental group, taught using the PBL model, and Class VII-E (25 students) as the control group, taught using conventional methods. Data were collected through problem-solving ability tests in the form of essay questions administered during the pretest and posttest. The hypothesis was tested using the Independent Sample T-Test. The results showed a positive and significant effect of the Problem-Based Learning model on students’ problem-solving abilities. This is evidenced by the t-value of 4.404 at a significance level of 0.005 and a significance value of 0.000, which is smaller than 0.005; thus, H₀ is rejected. Descriptively, the average posttest score of the experimental class (77.76) is higher than that of the control class (63.76), with a mean difference of 13.437. It can be concluded that the Problem-Based Learning model is effective in improving students’ problem-solving abilities through active engagement, inquiry, and the development of critical thinking skills.
Copyright (c) 2026 Nur Oktavia Sry Rejeki, Ratna Tanjung, Yul Ifda Tanjung https://creativecommons.org/licenses/by/4.0