The general characteristics of physical development: great changes in physical appearance, mature sexual development, increasingly sound cardiopulmonary function, development of central nervous system and early puberty development.
The general characteristics of psychological development (I think this should belong to the category of developmental psychology): the characteristics of psychological development can be explained from junior high school and senior high school universities respectively. If we must teach the mind, try to explain it from the aspects of thinking, cognition, emotion and morality.