ADHD is one of the most widely researched problems in child development, which has aroused unusual interest in recent years among the scientific community, but also among other stakeholders who live closely with this disorder, such as doctors, psychologists, teachers, educators and parents of these children. Despite significant scientific advances and its widespread dissemination, we are still referring to a subject shrouded in myths and misconceptions, which require clarification, so that students with ADHD can be better understood, thus safeguarding adequate school support for these children, and also ensuring an important contribution for those who deal with the problem on a daily basis, such as teachers, whose knowledge of this disorder is empirical and their actions/relationship with these students intuitive, and most of the time not the most appropriate. There is a consensus that the core symptoms of ADHD play a decisive role in the emergence of associated problems in the school context. At the same time, the literature highlights that the high degree of comorbidity in ADHD worsens its prognosis in this area. We need to know in order to intervene.