Some schools lack the structures necessary to change what happens in classrooms; schedules, departments, prescribed curriculum, and other systems are obstacles that are too great. Schools are social organizations, thus inherently political; changes in how teachers interact with students can be affected by the demands or threats of those who are more powerful. Some teachers are incapable of teaching students in the manner that is specified by alternative models. Some school leaders are incapable of helping the teachers learn about pedagogy or design organizational systems to implement alternative models of education.