Some Parents Challenge Enrollment Projections

Some parents have challenged estimates that, unless boundaries change, South Lakes High School will have 1,350 students in four years -- about half the number of nearby schools.
Some parents have challenged estimates that, unless boundaries change, South Lakes High School will have 1,350 students in four years -- about half the number of nearby schools. (By Hyosub Shin/Post)
By Michael Alison Chandler
Washington Post Staff Writer
Friday, February 8, 2008

To justify a major reshuffling of students bound for five high schools in western Fairfax County, school officials point to projections that show enrollment varying widely from one campus to another. But critics say those estimates could prove to be off the mark.

In a debate that has enveloped western Fairfax for months and will resume at a hearing tomorrow, some parents have challenged calculations that South Lakes High School in Reston will have 1,350 students four years from now unless attendance boundaries change.

That's about half the number projected for nearby Chantilly and Westfield high schools. Parents whose children attend those schools want them to stay there, in part because they have higher test scores.

In recent hearings, parents who favor the status quo have held up charts and offered alternative analyses suggesting that the South Lakes enrollment gap might not be as wide as the school system claimed.

"If they are basing a boundary study on this, we are concerned about how they got to these numbers," said Caitlin Vargas of Vienna. Her son would attend South Lakes rather than Madison High under the proposal. She and other parents have argued that the math underlying the boundary plan is "arbitrary" and could invite a lawsuit.

The School Board's hearing will be held at Luther Jackson Middle School in the Falls Church area. The board is scheduled to vote Feb. 28 on a plan to expand the number of neighborhoods that send children to South Lakes High, raising its projected student population by about 50 percent and lowering projections for Chantilly and Westfield in the Chantilly area and Madison and Oakton high schools in the Vienna area. Students now in high school would be unaffected.

Enrollment is one of many issues opponents of new boundaries are scrutinizing. Parents-turned-analysts have spent countless hours studying academic programs, bus route maps and financial records to counter the school system's numbers with their own. Their goal is to undermine the rationale for a plan that would affect several hundred students in the next few years and thousands more thereafter.

Leaders of the 165,700-student system, the region's largest, tout their track record on forecasts. Countywide projections have been within one percentage point of actual enrollment in nine of the past 16 years. In 2001 and 2002, projections were more than two points off. Officials acknowledge that predictions are increasingly difficult as growth in the county is driven by more subtle demographic changes than by housing construction.

"The more we know, the more we understand how difficult it is to be spot on with our projections," said Chief Operating Officer Dean Tistadt.

This school year, after several years of relatively flat enrollment, Fairfax received an unexpected influx of nearly 1,000 students, a bump officials say exemplifies harder-to-measure changes in the county. Loudoun and Prince William county schools also exceeded projections.

A staff demographer told the Fairfax School Board last month that the increase could be linked to growth in the number of Hispanic children entering kindergarten and the sinking housing market. Last school year, as home sales declined, fewer students withdrew from the school system than in previous years.

Accurate enrollment predictions are critical so officials can develop budgets, hire teachers, estimate building costs and draw attendance boundaries.

Parents opposed to new west county boundaries cite mistakes in enrollment projections elsewhere as evidence that the issue needs more scrutiny before any changes are made. Westfield High was well over capacity within a few years of opening day in 2000, and school officials have since expanded the facility. South County Secondary School, which opened in 2005 in Lorton, was several hundred students over capacity a year later, and boundaries had to be revised. School officials attributed the mistaken forecast for South County in large part to an unexpected increase in students who left private school or special public programs to go to the new school in Lorton.

In the past few years, school officials have sought input from several sources to improve their forecasting methodology, including researchers at George Mason University, a School Board-hired consultant and a citizen task force.

Officials have since hired a demographer, published accuracy rates of school-by-school projections and increased their use of geographic information system technology to improve their understanding of demographic shifts. But they have essentially stuck by their basic formula.

To crunch the numbers, the county examines several factors, including the average growth rate for each grade level at every school in recent years, input from principals about local trends, changes in academic programs, residential development trends and birthrates.

Regardless of whether enrollment in west county high schools strays from projections, some officials say the imbalances among them cannot be ignored.

"We know what [enrollment] is today, and we know where it was last year and the last couple of years," said Denise M. James, school facilities planning director. "Do you wait and see for two or three more years if the population goes up by 20 students? . . . There's a problem for the students who are there now."

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