Determination of Mistakes Made by Pre-Service Mathematics Teachers in Fermi Problem-Solving Performance and Solutions

One of the reasons why students fail in mathematics courses is that the problems used in the lessons are abstract. In this context, it is important to embody the problems used in the lessons. Fermi problems are open-ended problems, a type of problem that reflects real-life situations that are solved by making a series of predictions. In the future, with these problems involving real-life situations, it is today’s pre-service mathematics teachers who are primarily responsible for carrying out an effective teaching process in school mathematics. This research was carried out within the scope of the case study design, which is one of the qualitative research designs, which aims to determine the errors made by primary school mathematics teacher candidates in their performance and solutions to solve the Fermi problem. The study group of the study consisted of 44 pre-service teachers studying in the 4th grade in the department of primary school mathematics teaching in a province located in the southern region of Turkey in the 2022-2023 academic year. As a result of the research, it was concluded that the scores obtained by the pre-service mathematics teachers from the solutions of Fermi problems were not at the desired level, and the performance of the teacher candidates was at a medium level. From the error detection, it was find that the source of this situation is mostly due to the weakness in the dimensional estimation process.