LAUSR

Today, physics education aims to raise individuals who are inquisitive and critical, who can relate their knowledge with daily life, solve problems, and interpret events with a scientific outlook. In other words, it is expected for students to be able to understand the nature of science and use it accordingly. However, this is not a self-running process. For this process to reach the desired objectives, it should be carried out appropriately accompanied by various applications. One such application is thought to be an inquiry-based learning approach because this approach focuses on students’ knowledge acquisition process rather than focusing on bringing out an output (Llewellyn, 2007; Russo & Persano Adorno, 2018). Concentrating on students’ skills such as asking questions, critical thinking, and problem-solving, this process supports the development of these skills that students might need throughout their lives (van Uum et al., 2016). By developing students’ conceptual understanding, it is desired for students to have the chance to discover scientific concepts. At the same time, students are expected to have a more developed scientific attitude (Kang & Keinonen, 2018). It is also necessary for the focus of physics education to be altered; instead of memorizing concepts, students should be encouraged to learn in a manner where they make use of their cognitive and critical thinking skills by inquiry-based learning (Donohue et al., 2020). National Research Council [NRC] (2007) emphasized that different scientific methods should be utilized in the inquiry. Considering inquirybased learning and teaching in its most comprehensive form, this process is realized by the following steps: “asking questions and steering,” “generating a hypothesis,” “planning,” “researching,” “data analysis and interpretation,” “searching for and constructing a model,” “conclusion and evaluation,” “communication,” and “prediction.” The application of these steps in class can be done by the 5E learning model (Bell et al., 2010). 5E learning model is composed of five stages; namely, engage, explore, explain, elaborate, and evaluate. In the engage step, the aim is to draw students’ attention to a topic by a short activity or discussion. In the explore step, students develop hypotheses by making observations. In the explain step, students, Abstract. In this research, the teaching of mechanical waves was realized with inquiry-based learning; the aim was to determine the changes in students’ conceptual understanding of spring, water, and sound waves. It was designed as action research. The study group comprised 58 upper-secondary school students enrolled in 10th grade at an Anatolian uppersecondary school in Turkey. Data collection tools used in the research were the form for conceptual understanding of mechanical waves, semi-structured interviews, video recordings and photographs, student journals, and hand-made materials. Moreover, researchers designed an action plan that was composed of activities on spring, water, and sound waves. Descriptive and conceptual content analyses were utilized in data analysis. At the end of the research, it was determined that there was a change in students’ conceptual understanding of spring, water, and sound waves. Moreover, it was determined that teaching based on inquiry-based learning contributed positively to students’ learning. In this respect, it is thought that such applications should become widespread. There should be online training for lecturers which in return would contribute to students’ learning.