Investigation of primary school 4. students' number senses in problems based on four operations skills

The aim of this study is to examine the ability of 4th grade primary school students to use their number sense in solving problems based on four operation skills. The research was structured using the survey model, one of the quantitative research methods. The study group of the research consists of 521 4th grade students studying in three different primary schools in the city center of Isparta. The data of the study were collected using a 12-item number sense scale, which was prepared using the number sense components specified by Yang (1995) and using the "number sense scale with context" developed by Can (2017). In the number sense scale prepared by the researcher; there are 4 questions about the "understanding number sizes" component, 4 questions about the "flexibility in numbers and operations during calculation" component, 2 questions about the "utilizing the benchmarking point" component, and 2 questions about the "separating and recombining numbers" component. The data obtained within the scope of the answers given by the students were categorized and analyzed by the researcher and their frequencies were examined. The results of the research showed that the students preferred the rule-based solution way more in solving the problems in the scale. Also, it was determined that students benefited from number sense skills at a very low level in solving problems. When the performances of the students in the number sense components were examined, it was seen that the component that they used the number sense skills the most was "flexibility in numbers and operations during calculation", and the component that they used the number sense skills the least was the component of "separating and recombining numbers". In addition, the results of the research revealed that the questions in which the students preferred the rule-based solution the most were related to the "separating and recombining numbers" component, while the questions they preferred the least and were left blank the most were related to the "utilizing the benchmarking point" component.