Teachers play an essential role in supporting children with attention-deficit hyperactivity disorder (ADHD) and are often responsible for implementing the classroom-based interventions designed to bolster the academic and behavioral success, and the socio-emotional development of children with ADHD in schools. Unfortunately, several studies suggest teachers are inadequately prepared to take on this role. Evidence suggests there are widespread gaps in teacher knowledge about the meaning of a diagnosis of ADHD and evidence-based interventions used to support children with ADHD in schools. The main purpose of this study is to examine the effectiveness of a virtual, self-paced professional development seminar for preservice teachers. The webinar will be aimed at improving preservice teacher knowledge about the diagnosis of ADHD, characteristics of students with ADHD in the classroom, and evidence-based interventions that can be used to alleviate academic and behavioral problems often experienced by students with ADHD. The webinar also aims to increase preservice teachers' self-efficacy as it relates to supporting children with ADHD.