The article considers that in the school field the alliance of power and knowledge is usually formed and makes some power technique, which conduces many phenomena such as self-controlling and self-negating of the subjectivity of students, and causes the underprivileged groups. But at the same time, in the transformation of many relations of position in the school field, the controlling with power is not always effective. The expectancy of the controlling with power often ends without any results, which produces the change between the underprivileged groups of teachers and students. The article shows that it is an important reason that the power or power technique can not be understood and used rightly in the process of education.