Asian Journal of Science Education, Vol. 5. No. 1, April (2023) 90-101 e-ISSN 2715-5641 Asian Journal of Science Education Journal homepage: http://jurnal.unsyiah.ac.id/AJSE/ Development of Student Worksheets Based Inquiry using PhET Simulations to Enhance the Curiosity Attitude of High School Students Roni Jarlis 1* , Juli Supriyanti 2 , Fildza Arief Syuhada 3 , Ananto 4 , Taufiqqurahman 5 , Santi Diana Putri 6 , Putri Rahmi 7 1,2,3,4,5,6,7 Department of Agroindustry, Padang State University, West Sumatra – Indonesia *Corresponding email: ronijarlis@fmipa.unp.ac.id. (Received: 27 February 2023; Accepted: 27 June 2023; Published: 28 June 2023) ABSTRACT The research aims to develop inquiry-based worksheets which are expected to increase students' curiosity about gas kinetic theory material. The inquiry approach method was developed with steps, giving problems, formulating problems, hypotheses, experiments, collecting data, analyzing data, and making conclusions. The method used is the ADDIE development method, which analyzes, designs, develops, implements, and evaluates. Developing inquiry-based worksheets and testing the effectiveness of these worksheets in the learning process. The research subjects were 22 class XI students of SMA N 4 Sijunjung. The instrument used was a student worksheet and a curiosity attitude questionnaire. Assessment of the student worksheet was carried out by validation tests of media experts, material experts, and questionnaires for teachers. The validation results of media experts showed 92.30% (very good), and media experts scored 90.21% (very good), while trials on teachers and students showed scores of 86.13% and 89.16% (very good). The results of the student worksheet effectiveness test used the medium criterion N-Gain test, value <g> 0.32. This shows that inquiry-based worksheets equipped with Phet simulations deserve to be good teaching materials and can increase students' curiosity in high school physics learning on the kinetic theory of gases. Keywords: student worksheet development, inquiry, curiosity attitude, phet simulation INTRODUCTION The success of learning is largely determined by the design of teaching materials and the methods used in the learning process. In the learning process, it is very important that the name of the syllabus, learning implementation plans, teaching materials, or learning media and assessments. All of that aims to achieve effective and conducive learning outcomes and improve students' scientific attitudes toward learning outcomes. Instructional media guides used by students to obtain information in the learning process are made in the form of student worksheet-based inquiry. Student worksheet contains instructions for students to carry out activities in a structured manner (Wulandari et al., 2017). The preparation of student worksheets is based on the characteristics of the curriculum, materials, and students' cognitive abilities, and the student worksheet instills a