Teacher Evaluation Can Improve Teaching, Learning

A paper just published "http://educationnext.org/can-teacher-evaluation-improve-teaching/" shows that teacher evaluation alone can improve teacher performance. Curiously multiple evaluations improve performance significantly further.

This is important because outside just teaching itself for the first couple of years, nothing else has been shown to improve teachers' performance anywhere near as much. 

This makes sense if you think about it.  People act differently when observed.  For instance, people are much more likely to wash their hands in a public rest room if others are present.