Unless forced to, I don't write about entire school systems. They are often too big and bureaucratic for me, and the school board meetings -- hour after hour of minuscule rule changes and pointless discussion -- are torture. I tell everyone I am a classroom reporter. I pride myself on my infrequent contact with superintendents and school board members.

Unfortunately, despite my ignoring them, school systems are still with us. I have come into possession of two studies that attempt to explain what helps them succeed. Because one of the studies is about Fairfax County, I feel obliged to discuss them, as long as everyone understands that this is not going to be a regular thing.

The broader of the two studies, "Power to the Principals: Decentralization in Three Large School Districts," by UCLA management professor William G. Ouchi, will come out this spring in the journal Organization Science. The narrower study, about Fairfax County, is a short book, "Education Empire: The Evolution of an Excellent Suburban School System" ($21.95 at Amazon.com), by University of Virginia education professor Daniel L. Duke.

Both studies say that one way to improve student achievement in large systems is to give principals more power. Duke argues that what he sees as Fairfax County's success in educating rich and poor students has come from decentralizing the education of students with disabilities and letting schools choose demanding programs.

Ouchi's prescription for districts is much more radical. He praises the decentralization program created in 1976 by Mike Strembitsky, the superintendent of the Edmonton, Alberta, schools, and reports significant improvement in two American urban districts, Seattle and Houston, that adopted the Edmonton model.

Please take a moment for a note of caution from me, the reluctant reporter on school systems. It is difficult, indeed often foolhardy, to compare school systems with one another and declare why some are doing better than others. So many factors affect achievement -- poverty level, cultural background, administrative habits, state funding formulas, union strength, taxing authority, school board politics -- that it is impossible to decide conclusively what changes have had what impact. That is why I prefer to focus on individual students and individual schools.

But Ouchi and Duke are serious scholars presenting their results, not making claims. What they say about why these four systems have done well deserves close examination, even if I don't have any great hope that they have found what will cure all ills.

Duke makes no secret of the most important reason for the high achievement of Fairfax County students -- most of their parents have good jobs and good educations. As he notes on Page 1: "Fairfax County, of course, is not just any suburban area. It is one of if not the wealthiest counties in the United States."

But there are many affluent school systems that have not done nearly as well as Fairfax in educating low-income and minority students. Some of the county's schools, such as Stuart and Mount Vernon high schools, have high poverty levels, and yet their students do well in demanding programs such as International Baccalaureate and Advanced Placement. Fairfax has seen good results from giving its low-performing elementary schools more resources and longer school days, and 92 percent of its students with disabilities graduate with traditional diplomas.

Duke titles one section of the book "The Best School System in America," using quotation marks to emphasize that this is just an opinion (though it's one that I share). Although he singles out Fairfax, there are districts that rival Fairfax's quality, such as its Maryland neighbor Montgomery County, and many others that would do well, too, if they had its $1.8 billion budget.

But Duke's analysis of what else sets Fairfax apart is interesting. He says that Fairfax's administrators and school board members have high expectations for the school system, read the latest research and are often ahead of most districts in embracing promising new methods. The school system benefits from being relatively stable, with few crises or political battles, and is thus more willing, Duke says, to make serious changes and stick with them.

Fairfax leaders' approach to change, Duke emphasizes, is usually well-balanced. "They understand that the end result often must be judicious compromise, a balancing of competing interests," he says.

Ouchi ignores the middle-of-the-road approach and investigates a policy shift that most systems could not even imagine. Strembitsky, the Edmonton superintendent, created an accountability system a generation ago in which schools are rated not only by test scores and budget performance, but also by satisfaction surveys of their employees, students and parents. Parents can send their children to any school in the system, and the system funds each school based on a formula that gives more money to schools with more children who are poor, gifted, learning-disabled or not native English speakers.

That means that some students bring five times as much money with them as other students, and the principals and their staffs decide how to spend it. If the students don't come, they have nothing to spend, so they become very sensitive to what parents want from their schools. Their annually published test scores and satisfaction results are key to their survival.

Ouchi says that Houston and Seattle had impressive results when their school boards and superintendents adopted this approach in the 1990s, but there are many powerful reasons why so few school systems have followed the model. Money is power, and most school board members and superintendents of systems where spending decisions are made at headquarters don't want to give it up.

But if the Edmonton model continues to succeed, and academic achievement becomes, as the reformers promise, the basis on which school administrative decisions are made, other districts, including even Fairfax, might have to show more interest. There are, after all, some learning measures by which Fairfax does not look as good as many people think it should.

And if giving parents a choice of schools, assigning different dollar amounts to students based on what it costs to teach them and giving principals the responsibility for spending that money produces better student achievement, I might have to start taking school systems and what they do more seriously.

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