Integrating generative artificial intelligence (genAI) tools into education holds considerable potential for enhancing instructional practices. This study aimed to develop a scientifically sound instrument to assess pre-service and in-service teachers’ acceptance and intended use of genAI tools across two distinct application contexts: (a) as technological aids for lesson preparation and lesson follow-up, and (b) as a media-didactic element in classroom settings. Based on the Unified Theory of Acceptance and Use of Technology (UTAUT), a new questionnaire was designed and subjected to psychometric evaluation. Data were gathered from N = 123 pre-service and in-service teachers. Confirmatory factor analysis supported the hypothesized factorial structure of pre-service and in-service teachers’ attitudes and intentions, yielding largely satisfactory model fit indices. An analysis of the scales’ internal consistencies using McDonald’s omega demonstrated good reliability. Furthermore, six out of eight more nuanced subscale measurement models demonstrated adequate to good model fit indices, reinforcing the value of a context-sensitive, differentiated approach to understanding genAI acceptance. The internal consistencies of the subscales were largely good. Overall, the study contributes to the growing body of research on AI in education by introducing a reliable and partially validated instrument to measure (prospective) teachers’ acceptance and intended use of genAI.

Keywords: Artificial intelligence (AI), Generative AI (genAI) tools, Unified Theory of Technology Acceptance and Use of Technology (UTAUT), Instrument development, Validity, Reliability, Pre-service teachers, In-service teachers.