With the development of science in the 21st century, students' learning difficulties have become the focus of research. In addition to physical disabilities, more and more attention is being devoted to cognitive impairments of various cognitive-functional levels. In regards to this, it is necessary to adapt the teaching materials in a way that they are understandable to all students. The thesis will define the concept of students with impairments, as well as accompanying terminology and legal regulations which govern the relationship of student inclusion in educational programs. The state of integration in the Republic of Croatia will also be examined. Furthermore, the thesis will present methods of adapted teaching according to the type of impairment that is present, and within each subgroup of impairments, their characteristics and assistive technologies that would facilitate the teaching process will be explored. Special emphasis will be placed on the presentation of formal, non-formal and informal forms of professional development and education of teachers and the need for them. The role of teachers in adapting teaching will also be considered in a way that summarizes research conducted from a student perspective. As part of the thesis, a research will be conducted in which teachers of primary and secondary schools in the Republic of Croatia will be included. The presence of the need for teaching adaptation will be researched, as well as the methods that the teaching staff incorporates into the mentioned teaching adaptation. The results of the research and their implications will be discussed within the conclusion of the thesis.