As discussed in detail in previous chapters (especially in Chapter 1), boys and male teens with attention deficit/hyperactivity disorder (ADHD) exhibit symptoms that result in significant difficulties at home, in school, and with peers. Symptoms of ADHD fall along two clusters, those of hyperactivity/impulsivity and those of inattentiveness/disorganization, and males with ADHD exhibit problems in either or both of those categories. In fact, as research has shown, males are especially likely to exhibit symptoms from both clusters, whereas females with ADHD are more likely to exhibit inattentiveness and distractibility only (Barkley, 2006).