Investigation of the Effectiveness of the Problem-Based Learning (PBL) Model in Teaching the Concepts of "Heat, Temperature and Pressure" and the Effects of the Activities on the Development of Scientific Process Skills

This study aims to reveal the effectiveness of the problem-based learning (PBL) model in teaching the concepts of heat, temperature and pressure, as well as the effect of the activities on the development of scientific process skills. For this purpose, the change in the academic achievement levels of the students constituting the sampling group was tried to be determined with a pilot application designed based on this model. The research was carried out on a single group based on a pretest-posttest applied quasi-experimental design. Teaching activities addressing the concepts of heat, temperature and pressure and designed according to the PBL model were carried out in a private school over a two-week period. In this context, a unique problem situation was designed, in which two brothers watched and discussed the volume changes of small and large inflated balloons with the effect of temperature, and student-centered activities were carried out, in which demonstration, lecture, question-answer and discussion methods were dominantly used. The problem situation, which includes important connections such as gas, gas pressure, temperature and heat concepts, the relationship between heat and temperature, and the relationship between temperature and pressure, which are known to be quite difficult to understand by 8th-grade students, were implemented sequentially in a single scenario. From the pretest-posttest results, it was determined that there was a significant positive difference in the academic achievement levels of the students constituting the sampling group after the application, and there was a very large difference between the pretest-posttest scores (66.0-92.5). As a result, it can be said that very striking results can be achieved in understanding the selected concepts and the relations between them, with the scenario and appropriate teaching activities designed in a sufficient time based on the problem-based teaching model, and especially the effective and interactive use of demonstration and question-answer methods. Moreover, the results of the pre-test and post-test related to the integrated science process skills test showed that the application in question led to a positive and significant difference in the scientific process skills of the students.