Teenage children sleepy may be overworked, hypothyroidism, anemia and other causes. 1. Physiological factors: overwork, dry and hot climate, long time in the dark and quiet environment, insufficient nutritional intake, lack of sleep at night, low interest in life learning, obesity, lack of exercise and other physiological factors may lead to teenage children sleepy. 2. Hypothyroidism: hypothyroidism leads to a decrease in thyroid synthesis and secretion, low basal metabolic rate, and insufficient utilization of tissue cell energy consumption, so the above symptoms appear. 3. anemia: iron deficiency anemia, megaloblastic anemia, thalassemia, chronic blood loss and other factors lead to a shortage of red blood cells, hemoglobin, chronic ischemia and hypoxia and the above symptoms. Teenage children sleepy may be related to a variety of factors, it is recommended to consult a doctor for a clear diagnosis.