Curiosity and the need to explore the world are qualities common to all children. The purpose of Natural Science classes in lower grades of primary school is to introduce students to the exploration of the world and comprehension of the nature that surrounds them. In that way, students are encouraged to learn and develop the skills and abilities necessary to navigate the modern world. The role of the teacher is to encourage students’ curiosity and their need to learn and explore. The best way to accomplish this is by using natural science methods and procedures. One of the most important natural science procedures in Science and Social Studies classes is conducting experiments. Students’ research skills start developing intensively in the third grade of primary school, when they learn about the experiment and the different phases of experimental procedures. Afterwards, students are ready to independently explore nature and empirical learning. The main aim of this diploma thesis is to determine the frequency of using experiments in Science and Social Studies classes. The thesis also aims to examine teachers’ competences, opinions, and overall interest in conducting experiments in the classroom. The theoretical part of the thesis determines the aims and purpose of the experiment, explains its demonstration, and discusses the importance of using experiments in Science and Social Studies classes. Furthermore, it gives an overview of the basic determinants of the experiment in the curriculum for compulsory education, and lists the handbooks and workbooks that contain tasks related to the application of experiments. The participants in this research were primary education teachers from Croatia (N = 103). An online questionnaire, designed specifically for the purposes of this research, was used to collect data. The research has shown that teachers conduct experiments with the third- and fourth-grade students more often than with first or second graders. Most participants (over 50%) consider themselves competent to conduct experiments in the classroom. The research has also shown that teachers show great interest in the application of experiments in Science and Social Studies classes. In addition, most of them believe that the experiment is a significant natural science procedure that should be conducted often.