In heterogeneous classrooms which attend children with different abilities and needs, it is of utmost importance to manage classroom discipline. The aim of this research paper is to examine the frequency of application of strategies for managing classroom discipline in the work with students with ADHD disorder and its age relatedness, years of work experience in the profession and the weekly number of lessons to be taught. 242 primary and secondary school teachers from the five counties of the Republic of Croatia: Koprivničko-križevačka, Međimurska, Primorsko-Goranska, Sisačko-Moslavačka and Varaždinska, participated in the survey. They assessed pupils for whom they felt that they had certain symptoms of undesirable behavior. The research was conducted in two phases. The first phase of the research was to complete the Checklist for the student while the second phase of the survey was to complete the Questionnaire for a student who came into the sample based on the Check List of Behaviors. As we can see from this research paper, eachers most commonly use strategies of positive behavioral support in managing behavior of students with ADHD. Younger teachers, in applying strategies in classroom management use more negative support strategies than older teachers. Although, teachers who have more years of work experience in the profession are more likely to use the method of conflict resolution. The results show us that there is a statistically significant correlation between the frequency of application five strategies for managing classroom discipline in the work with students with ADHD disorder and the teachers weekly number of lessons to be taught.