It is a well-established fact that teacher quality is the biggest school-level factor related to the success or failure of students and thus, the achievement gap between students. A 2006 study in Los Angeles, CA found that when students were taught by the top 25% of the most effective teachers, the students advanced approximately five percentile points each year compared with their peers. Those taught by teachers in the bottom quartile of effectiveness, lose, on average, five percentile points, compared with their peers. However, having access to quality teachers would not be possible without a skilled and dedicated principal.  Continue reading