o:39906 Mistakes In The Assessment Of Students' Work And Achievements – Perception Of In-Service And Pre-Service Teachers en Abstract: The focus of our research is placed on one of the key aspects of the problem of fairness in assessment in the future professional activity of teachers – mistakes in the assessment of students' work and achievements, due to the fact that previously conducted didactic analyses have raised a series of dilemmas about the purpose of assessment, about fairness in assessment, about the objectivity of evaluators, about didactic competencies of teachers, etc. The aim of the research is to analyze how mistakes in the assessment of students' work and achievements are perceived by in-service and pre-service teachers. In search of an answer to questions related to mistakes in assessment, perceived as one of the aspects of the problem of fairness in assessment in the future professional activity of teachers, a qualitative methodology was applied - " workshop as a research methodology", within which semi-structured interviews were used with the intention that in-service and pre-service teachers would reach mutual agreement by listing and commenting on three mistakes related to the teacher factor and the student factor. The questions concerned grading mistakes related to the teacher factor and grading mistakes related to the student factor. Data obtained on a snowball sample of 107 active teachers from primary schools in the territory of Serbia and 107 future teachers, students of the second year of undergraduate studies, in the study program for teacher education of the Faculty of Education of the University of Belgrade, were analyzed using phenomenological interpretive analysis. The results of the analysis pointed to the following mistakes related to the teacher factor: Lack or inadequacy of teachers' didactic competencies, i.e. assessment of inadequate ways of learning. Mistakes related to the student factor concern the lack of motivation for learning and some personal characteristics of students. Reasoning about the observed mistakes in assessment by inservice and pre-service teachers provides an opportunity to implement pedagogical and didactic measures directed toward enhancing objectivity in the assessment of students' work and achievements in teaching practice. At the same time, these findings indicate the need to develop competencies for objective assessment, in order to ensure fairness in assessment in future professional activity. Keywords: mistakes in assessment, formative assessment, didactic competences, teacher, student. 1552099 10.5937/IstrPed2603290R 1552101 2217-7337 2026-10-01T12:38:50.094Z 44 yes 46 Vera Radović University of Belgrade, Faculty of Education 0000-0002-1525-9547 Nataša Tančić University of Novi Sad, Faculty of Philosophy person 0000-0002-0930-2924 Milica Marković University of Belgrade, Faculty of Education person 0009-0008-4018-6774 application/pdf 198597 https://phaidrabg.bg.ac.rs/o:39906 no yes 1 70 92000001 2026 11A42 Research in Pedagogy 16 3 290 305 2026 https://research.rs/wp-content/uploads/2026/09/05-Radovic-Tancic-Markovic-27-9-2026.pdf