Development Worksheet Integrated PhET Simulation to Improve Critical Thinking Skills in Junior High School

. Integrating technology has a positive impact on science learning. Technology multiplatform can be used as a didactic tool is physics education technology (PhET). This study aims to develop worksheet integrated PhET simulations. The development adopted the 4D model. The designed activity aims to engage students in critical thinking. The instrument for measuring critical thinking consists of 5 questions based on the critical thinking aspect: interpretation, analysis, evaluation, inference, and explanation. Content and media experts and two practitioners validated the media. The validation result shows a V index between 0.80 - 1.00 for all aspects with very high categories. The readability test was administered to 20 students and gained very good results. The effectiveness test was conducted on two different classes. The experiment class uses a worksheet integrated PhET, while the control class uses a worksheet without PhET. Students in the experiment class had higher critical thinking skills scores than those in class control. It can be interpreted that using worksheet-integrated PhET affected students' critical-thinking skills. The results of this study can be used as a reference for integrating technology into science learning .


Introduction
Physics, as part of science education, is a subject that proves challenging for students.In some literature, it is mentioned that students perceive physics as a subject with complex and abstract concepts (Asriadi & Istiyono, 2020;Sutarja & Wulandari, 2021).Consequently, teachers must be adept at selecting appropriate teaching strategies to ensure good learning achievements.
The tremendous development of science and technology also affects education (Stone & Zheng, 2014).Integrating technology into education can create an interactive and enjoyable learning environment (Rahmat, et al., 2023).Students are more engaged in learning when recent technology is involved.Technology facilitates students to learn independently and explore their skills (Schmidt-Crawford et al., 2018) Technology has the potential to provide exciting experiences and opportunities for designing realistic, engaging, and enjoyable learning environments (Abdusselam & Karal, 2020;Cai et al., 2017).
Physics has many abstract concepts that are difficult for students to understand (Fidan & Tuncel, 2019).Teachers must teach how to sequentially apply the physics methodology to develop students' ability to apply similar strategies in everyday life.The low ability of students to understand abstract concepts and the lack of activity of students in the learning process requires solutions that increase student motivation and achievement (Fajari, 2020).Many students with a low understanding of physics become passive in learning activities.Using interactive media motivates students in learning activities and creates a learning environment transfer of verbal knowledge (Puspitarini & Hanif, 2019).
A free app available on multiplatform called physics education technology (PhET) is one of the interactive simulations that is being used in teaching science, especially physics and chemistry.PhET was developed by University of Colorado Boulder (Salame & Makki, 2021).PhET is usually implemented in secondary school to design and use of interactive simulations (Prima et al., 2018).PhET have various topics in physics and reallife applications, also including simulations on chemistry topic.It increases students interest to doing simulation tu support experimental activities.Hence, PhET simulation has a vast potential to be used as a learning medium in science learning (Handayanti et al., 2020).
Experimental activities are essential in learning physics because they can increase the interaction between teachers and students.In addition, experiment activities can also develop scientific abilities and investigation processes and help understand concepts in the real world with applicable theories (Nanto et al., 2022).Integrating PhET into science learning help students to learn by exploring directly, creates an animated for abstract fact or invisible phenomena such as atoms, electrons, photons, and magnetic fields (Tuhusula et al., 2020).Students with critical thinking skills can solve problems encountered by discovering phenomena of everyday life (Dwyer et al., 2014;Firdaus & Wilujeng, 2018;Marin & Halpern, 2011).
In the era of the industrial revolution, with significant growth of advanced technology, students need to be prepared with critical thinking skills (Terblanche & De Clercq, 2021).Nowadays, school curricula, including science learning, should accommodate critical thinking skills cultivation.Critical thinking skills can increase when the stimulation provided is concrete and has been experienced by students directly (Kurniawan & Kuswanto, 2021).Integrating technology into science classroom to engage students in learning activies and developing their critical thinking skills.In this study, a physics learning activity integrated physics education technology is designed and implemented in the classroom.Students collaborate to analyze the rope wave simulation using PhET on their smartphones.This study aims to implement worksheet-integrated PhET and their effect on students' critical thinking skills.

Methods
The type of study is research and development (R&D) with a 4D model, which consists of four steps: define, design, develop, and disseminate (Thiagarajan et al., 1974).The stages of this research are shown in Figure 1.The participants of this study include experts and practitioners.A feasibility test involving content and media experts and two practitioners was conducted in the developed media.The experts were selected according to their areas of expertise.The media readability testing was carried out by involving 20 students in junior high school.Then, the effectiveness test was carried out in two classes.The demographic of participants is shown in Table 1.The data collection instruments in this study are media validation sheets (content and media) and the questionnaire for students.The media validation sheet assessed the developed worksheet integrated with PhET as a learning media.Product assessment was divided into three parts, such as the assessment of content experts, media experts, and practitioners.The difference between the three parts is in the aspect being assessed.The validation sheet used a 4-point Likert scale, explaining each score shown in Table 2.The readability test comprised ten questionnaires and one comment column for students.The questionnaire used the Guttman scale.The data obtained were nominal, with a score of 0 for a negative answer and 1 for a positive answer (Conejo et al., 2021).The data obtained from the validation sheet and questionnaire were quantitative data and qualitative.The quantitative data were in the form of scores assigned to the developed worksheet-integrated PhET, while the qualitative data were comments and suggestions for improving worksheet-integrated PhET.To determine the effectiveness of the developed media on critical thinking skills tests were carried out in 2 classes (See Table 1).This effective test uses five essays to evaluate critical thinking skills for pre-and posttest.Question indicators in this study are shown in Table 3.This study used quantitative data from the validation results of the developed media and student readability.The media content validation testing used Aiken's V based on the results of n-validators.Aiken's V equation is as follows in equation (1) (Lewis.R. Aiken, 1985), and the criteria valid is shown in Table 4.To identify readability tests using a questionnaire with the Guttman scale.The assessment result was calculated for each indicator's average value.The calculation of the average score used the equation ( 2).
(2) With ∑x is the sum of all respondents' scores for one indicator, and n is the number of respondents.The analysis of this readability test used the ideal standard deviation (ISD) with the criteria presented in Table 5, with the X value being each indicator's average score.Then, effective test data aims to evaluate critical thinking skills using rubrics for essays.Furthermore, an analysis was carried out using the Microsoft Excel and IBM SPSS Statistic 25.

Define Stage
The first stage in the developed media is defined, where the researchers determine the objectives of developing worksheet-integrated technology.The aim of developing the media paid attention to the needs of students, ease of learning, and integration of technology into the learning process.Based on student feedback, students rarely use worksheets in experiment activities, and lab equipment is incomplete.Occasionally, students search the internet to find learning materials because learning in the classroom is boring, and students have difficulty understanding physics concepts.
The development worksheet integrated with PhET was designed to facilitate students into doing experiment activities at school or home and practice questions that could be done repeatedly.This worksheet is expected to satisfy students' needs to be able to do experiments.Integrating PhET help students to simulate physics concepts and repeat them over time.The design aims to facilitate critical thinking skills in learning physics.

Design Stage
The next stage is design, where researchers are designed and set the worksheet integrated with PhET.The worksheet was designed to facilitate students in understanding the concept of vibration and waves and to facilitate critical thinking skills in physics learning.The language used in the developed application is Indonesian.The first step in the worksheet's design and cover of the worksheet is shown in Figure 2.

Figure 2. Design of worksheet
Based on the worksheet design, the worksheet was built using Canva.Then the worksheet will be converted into .pdfformat and printed out so that it can be taken with you during experimental activities.The worksheet also contains a guide to using PhET simulation in experimental activities, as shown in Figure 3. PhET is a multi-platform application used on Android, iOS, and Web.
Figure 3 shows the steps for using PhEt in experimental activities.Changing variables to fill the observation table can improve students' critical thinking skills.The visualizations displayed on PhEt also aid visual representation skills.Integrating technology into learning activities is expected to improve students' critical thinking skills.

Develop Stage
The developed worksheet integrated PhET with the material discussed is vibrated and wave concepts.After the worksheet is designed, the next stage is developed.The developed worksheet must assess expert validators, including content and media.The result of the validation of expert content and media is presented in Table 6.Results of validation by media and content experts were shown that all indicators have a very high category.It can be interpreted that worksheet integrated PhEt is suitable for use in learning science in class.Besides, worksheet-integrated PhET also assessed by two practitioners, and the result is presented in Table 7.After validating the worksheet integrated PhET, the next test is the readability test with a limited participant, only 20 students from 9 th grade in junior high school.Each student is asked to install and use PhET according to the guidelines in the worksheet.Then students were asked to fill out responses to integrating PhET into the worksheet for science experiment activities.The result of students' responses is shown in Table 8.The result of the readability test is categorized as very good with a value of Xi = 0.5 and ISD = 0.167, and thus the value of Xi + 1.8 ISD = 0.8.The result obtained exceeds the value of 1.00 > 0.8.After the validation and readability test result was declared good and feasible.After that, apply and disseminate worksheet integrated PhET in learning activities.

Disseminate Stage
The dissemination stage includes registering product copyrights, distributing worksheets to teachers and students in the Bandung district, and using worksheets integrated with PhET in learning activities.There are two classes for comparison (See Table 1).Class Experiment using worksheet integrated PhET and class control using worksheet without PhET.Each class was given the same pre-test and post-test questions.Within the aim of the study, the critical thinking skills of the students were determined.Detailed information on students' critical thinking in classes experiment and control can be found in Figure 4.A pairwise comparison analysis was conducted to determine any significant difference between the students in classes control and experiment regarding their critical thinking skills.The result can be found in Table 9.The mean difference is obtained from the mean value of the pre-test minus the average value of the post-test.The negative sign indicates that the average post-test score is higher than the pre-test.The mean difference in experiment class is -37.18, and control class is -21.40.Based on the pre-test and post-test scores, the result interpreted a significant increase in critical thinking skills in classes experiment and control.This is clarified by the significance value in the classes experiment and control are 0.000, which mean that the significance value is < = 0.05. the result can be interpreted that class experiment who uses worksheet-integrated PhET has significantly different critical thinking skills than those using worksheet without PhET.Integrating technology into science learning positively impacts student academic achievements (Dunn & Kennedy, 2019).Utilizing technology with various information and communication can effectively support students in learning process (Sudarsana et al., 2019).Integrating technology into science learning also facilitates independent learning, enabling students to explore subject materials and their skills (Kopzhassarova et al., 2016;Rahmat et al., 2023).Besides, learning activities related to students' daily life can help construct local knowledge into scientific knowledge (Rahmat et al., 2023;Rahmi & Rosdiana, 2018).
120| Jurnal Pendidikan Sains Indonesia (Indonesian Journal of Science Education), 12(1), p. 111-123, (2024) The significant difference between classes experiment and control in critical thinking skills shows that using worksheet-integrated PhET scores higher than using worksheet without PhET.These results are relevant to research that PhET positively impacts learning achievement compared to traditional methods such as textbooks (Mahtari et al., 2020;Muzana et al., 2021;Prima et al., 2018).PhET in physics learning can improve critical thinking skills (Dasilva et al., 2019;Putranta & Kuswanto, 2018;Ramadan & Astuti, 2020).PhET can visualize objects and show the influence between variables (Tuhusula et al., 2020).Students can easily interpret problems with the help of simulation object and represent physics concepts so that students easily understand them (Putranta & Wilujeng, 2019;Yuliati et al., 2018).

Conclusion
This study aims to develop worksheet-integrated PhET to improve students' critical thinking skills.Worksheet was assessed by validators consisting of content and media experts and practitioners.The result shows that the developed media is in the 'very high' category.The readability testing involving students scored in the 'very-good' category.Also, this study identify the effectiveness of worksheet-integrated PhET.Students in the experiment class had higher critical thinking skills scores than those in class control.It can be interpreted that using worksheet-integrated PhET affected students' criticalthinking skills.Limitation of the study is implementing PhET in wave topic only.Suggestions for further research can use PhET on other topics, especially physics concepts that are difficult to do experiments in the laboratory.

Figure 1 .
Figure 1.4D Model Stages 's validation index r = scores by validators l0 = lowest validation assessment score (this case = 1) n = number of validators c = highest validation assessment score (this case = 4)

Figure 4 .
Figure 4. Average scores of the pre-test and post-test in experiment and control classes

Table 1 .
Demographic of Participants

Table 2 .
Criteria Score of Likert scale Point Criteria

Table 3 .
Detail instrument research EvaluationStudents can evaluate phenomena in daily life and relate to them Inference Students can create statements or conclusions regarding the results of the investigation based on relevant information Explanation Students can explain the reasons for the arguments, evidence, or other information about the phenomenon.

Table 6 .
Result of validation by media and content experts

Table 7 .
Result of validation by practitioners

Table 8 .
Result of a readability test

Table 9 .
Difference between critical thinking skills of students