Investigation of pre-service secondary school mathematics teachers' number sense strategies

The aim of this study is to examine the number sense-based strategies used by pre-service secondary school mathematics teachers while solving the problems. Designed as a case study, one of the qualitative research methods, the participants of this study consist of 18 pre-service secondary school mathematics teachers' studying at a state university during the 2022-2023 academic year. The assessment instrument, prepared by the researcher with the help of studies in the literature and expert opinions, consists of 14 questions. These questions are based on the six components of number sense used in the classification by McIntosh et al. (1997). The instrument was administered to the teacher candidates in the form of semi-structured individual interviews. The data comprise audio recordings taken during the individual interviews and the notes that the teacher candidates wrote on paper during the problem-solving process. Descriptive analysis was used for data analysis. These data were analyzed in line with the study's purpose to examine pre-service teachers' strategies towards as number sense-based and algorithm-based strategies when solve the problems. The results of the study indicated that the pre-service teachers mostly use algorithm-based strategies.