I agree, to a certain extent. First off all, the conditions in schools affect what learning can occur there. A school's budget includes money for supplies and teachers, and schools with higher budgets can hire more experienced teachers, leading to more learning.
The atmosphere of a school makes a big difference. When a school is negative, teacher morale will be poor. Teacher morale has an impact on student achievement, because teachers are human and miserable teachers are not going to be as effective.
Studies have shown that a student population whose majority of students are of a competitive nature is more successful than one in which the majority is non-competitive. The influence of the competitive students upon the others has shown to be positive as non-competitive students in this environment rise in achievement.
Certainly, a faculty with a strong work ethic who set high standards do, indeed, obtain results that lackadaisical teachers do not. Afterall, the power of example should never be discounted. Discipline is also a key factor, for learning cannot take place in a classroon in which students cannot concentrate and be relaxed enough to comprehend what they hear and read. The "Lean On Me" movir exemplifies the power of example and discipline.
I agree that the administrator sets the tone as do concerned and caring teachers. Having a staff in place that has been in one school for several years provides stability, as well. For many students, school is the only place that they come to where there is such stability.
After nearly two decades of working in school systems, I do agree that factors within a school are the main influence on educational achievement. I would even argue that the attitude of staff alone is the main influence on educational achievement. Movies that depict real life teachers such as Ron Clark (The Ron Clark Story) and Jamie A. Escalante (Stand and Deliver) demonstrate the influence a teacher's attitude has on children's achievement, despite the community in which they reside. Stories about real-life administrators, such as Joe Clark (Lean on Me) demonstrate how the attitude and work-ethic of an administrator can influence the attitude of an entire staff. When everyone in the school, from teachers, to custodians, to lunch room staff, to secretaries and principals have high expectations for themselves and for the students in their school, students will rise to meet those expectations. Staff with positive attitudes are also more willing to work on other factors within the school, such as training in the most effective techniques, finding funding sources to give their students great educational experiences, communicating effectively with one another, appreciating the expertise of other staff, asking for help, etc.