When my son, Xiao Ming, started elementary school, his teachers reported that he was particularly active, looking around in class, often wandering off, making small movements, and failing to complete his homework on time when he got home, and his academic performance was deteriorating. Is Xiao Ming a naughty boy or a hyperactive boy? It is the nature of children to be active. They learn to understand and adapt to the world by observing, imitating, playing, playing and even arguing, and being “naughty and active” is just the personality of some children. However, attention deficit hyperactivity disorder, commonly known as “ADHD”, is the most common psychological and behavioral disorder of childhood and adolescence. It usually starts before the age of 6, and the symptoms become apparent during the school age, and gradually improve with age, and some cases can continue into adulthood. ADHD is not the result of poor parenting, nor is it the result of a child’s willfulness or disobedience. Scientific research has proven that it is related to central nervous system dysfunction and is influenced by psychosocial factors. What exactly is the difference between a child with ADHD and a child who is naughty and hyperactive? The hyperactive behavior of children with ADHD is often purposeless, more impulsive, and disorganized, with no end in sight. Naughty children often act with a purpose and have plans and arrangements; “naughty and active” children are often selective in what they do and when they do it, for example, in serious and unfamiliar environments, and naughty children have the self-control to keep to themselves and do not fool around. Children with ADHD do not have such self-control, and their “hyperactivity” is not selective in terms of content and occasions. In short, the main characteristics of children with ADHD are inattention, distractibility, hyperactivity, impulsivity, abrupt behavior, and disregard for consequences. When these manifestations are found from time to time and persist for up to six months, especially when the child acts inappropriately on more than two different occasions that they cannot control, they should go to the hospital as early as possible for further examination. It is best to detect and intervene in ADHD before the child starts elementary school, as this will have much less impact on the child’s academic and social functioning. It is understood that children with ADHD may have oppositional defiant disorder, anxiety, depression, insomnia, or conduct problems, so it is important to diagnose ADHD while also investigating other psychological disorders. After the diagnosis of “ADHD”, in order to prevent the child from carrying the psychological burden, doctors often do not put the disease on the child’s hat, but only provide targeted guidance and training on specific behavioral, learning or social problems, and give the child time to talk.