Children with hyperactivity disorder usually come to the attention of their parents and teachers during the elementary school years, but the major symptoms appear before the child is of school age or even during infancy and early childhood. The main manifestations are: 1. Attention deficit The attention deficit in children with ADHD is mainly due to low intentional attention, while unintentional attention is relatively hyperactive. Children with hyperactivity disorder are very susceptible to subtle external distractions and shift their attention, or focus their attention for a short period of time. 2, hyperactivity Hyperactivity is another major symptom of children with ADHD, which is manifested by children’s significant hyperactivity regardless of the occasion and without purpose. Most of the children with hyperactivity in infancy and early childhood, but after elementary school is more likely to attract the attention of parents and teachers. Children with the disease show obvious hyperactivity both at school and at home, such as: inability to sit still, making small movements in class, interfering with neighboring students, interrupting too much, making loud noises or chasing and playing regardless of the occasion. 3.Emotional instability, impulsive behavior Children with hyperactivity disorder are usually emotionally unstable, easily overexcited when they are happy, easily provoked and impulsive when they encounter trivial matters, often quarrels and fights with others, and cannot wait in games or activities that need to be carried out in turn. 4.Learning difficulties Children with ADHD are behind in their academic performance due to attention deficit, and may also have specific learning skills development disorders. 5.Other Children with ADHD may often be criticized by teachers and scolded by parents. Children with ADHD often lose their self-confidence and self-esteem and develop emotional and behavioral disorders, including anxiety (about 25%), mood disorders (20%), defiant disorders (50%), and conduct disorders (30%-50%).