What did you find about the relationship between school organization and school performance?

If school performance is gauged by student achievement, school organization is a major determinant of effectiveness. All things being equal, high school students achieve significantly more – perhaps a year more – in schools that are "effectively" organized than in schools that are not. Indeed, after the aptitude or entering ability of the student, no factor – including the education and income of the family or the caliber of a student's peers – may have a larger impact on how much a student achieves in high school than how a school is organized to teach its students.

We reached these conclusions after analyzing the gains made by roughly 9,000 students on standardized tests – in reading, writing, vocabulary, math, and science – administered first during the sophomore year of high school and then again at the end of the senior year. It is important to recognize that by analyzing the gains on these tests, as opposed to analyzing only the final level of achievement on the tests, we have probably improved our chances of measuring the effect that schools actually have on achievement. Most studies of student achievement analyze test score levels, not gains. By high school, however, levels of achievement are heavily influenced by a host of factors preceding the high school experience. Our study looks at a variety of factors besides the school experience too, but our measures of student achievement are not contaminated by prior influences; the gain scores reflect only the learning that has taken place during the high school years.

The influences on student achievement, besides school organization, that we examined included several that are generally beyond the control of schools – the education and income of the parents, the race of the student, the education and income of the families in the school (a proxy for peer group influences), and the aptitude of the student. We also examined some of the conventional influences over which the school has control – pupil-teacher ratios, expenditures per student, teacher salaries, graduation requirements, homework loads, disciplinary policies, and more. When all of these influences were examined Simultaneously, and in various combinations, most did not make a significant difference for student achievement. School resources and prominent school policies were not systematically related to student performance. This is consistent with the results of countless input-output studies that precede ours.

In the final analysis, only four factors consistently made a significant difference in achievement gains by high school students. In order of importance they were student aptitude, school organization, family background, and peer group influence. Over a four-year high school experience the difference in achievement that would be expected to result from being in the top quartile rather than the bottom quartile on each of these factors, all other factors being equal, are as follows: aptitude, one-and-a-half years of achievement; school organization, a little more than one year of achievement; family background, one year of achievement; and peer group Influence, less than a halt year of achievement. In short, school organization may be as important to student achievement as the influence of families, a major influence indeed.