Özet:

STEM activities include processes that involve different disciplines and produce solutions to the problems faced by students. In this study, it was aimed to develop a valid and reliable scale to determine teachers' self-efficacy perceptions of STEM activities. The study group of the research consists of 473 teachers (308 for EFA and 165 for CFA). The draft scale form, which was prepared in a 5-point Likert type with 51 items, was applied to 308 teachers. The data were presented to expert opinion by calculating item-total score correlation values. According to the findings, the draft form was transformed into a form consisting of 26 items. Then, exploratory factor analysis (EFA) was performed. According to the results of the analysis, six items were removed from the draft form. It was determined that the reliability coefficient (Cronbach alpha) of the scale form consisting of 20 items was 0.97 and it explained 64.569% of the total variance in the single-factor structure. Confirmatory factor analysis (CFA) was performed to determine the construct validity. As a result of confirmatory factor analysis, it was determined that the fit indices were provided at a high level. According to these results, it can be said that the scale is a valid and reliable measurement tool.