In the modern educational system, summative assessment is replaced by formative assessment. Formative student assessment involves the continuous monitoring of all parts of the educational process, providing students with feedback on achievements and aspects that the teacher needs to improve and adapt in their teching in order to adapt to the student. The emphasis is on individualizing assessment, differentiated teaching, applying different strategies, and empowering students for the process of self-assessment and managing their own learning. The aim of the research was to examine teachers' attitudes about formative assessment and competences for its implementation in teaching, the frequency of using forms of evaluation and self-evaluation in educational practice, and to identify difficulties in descriptive assessment. Over 115 classroom teachers from Karlovac, Primorsko-Goranska and Istria counties participated in the research. The results show that teachers are familiar with the term formative assessment, believe that this form of evaluation has advantages and that implementation is worth their effort, but at the same time they do not feel competent enough to implement it, which affects the frequency of use and choice of material. Lack of time is cited as the most aggravating factor for its implementation in teaching, as well as for carrying out descriptive assessment. Of the forms of assessment and self- assessment, they most often use self- assessment and peer assessment, which is consistent with the goals of formative assessment. At least when evaluating, they use self- assessment lists. The need for further education and professional development of teachers on strategies and forms of formative assessment is emphasized in order to effectively implement this form of evaluation as an integral part of the educational process in cooperation with students and parents.