Every few years, officials of the county government and its school system pour too much time and resources into a process that creates ill feelings among parents and children and headaches all around, all because no one seems able to predict with any degree of certainty where local classroom populations will bulge and where they will shrink.

School redistricting is inevitable, of course, but the seemingly endless need for wholesale changes to the map points toward systemic flaws.

School officials say they need to undertake a comprehensive redistricting of elementary schools that will entail a "cascade of movement" of students throughout the county to correct an imbalance between school populations in the east, which are generally above capacity, and those in the west, which has not seen the kind of residential growth they anticipated.

A severe downturn in the national economy over the past three years certainly threw a monkey wrench into any number of statistical models, but this isn't the first time school redistricting in Howard County has required not just tweaks, but major reshuffling.

Sometimes these plans become obsolete even before they take effect. A redistricting approved in 2006 had parents in Ellicott's City's Wheatfield neighborhood complaining that it would bus their elementary school-aged children through six different districts — including one for a new school being built practically in their front yards — before reaching their destination.

At the end of the 2002-03 school year, officials discovered that the projections they used in the redistricting plan to be implemented the following year were miscalculated, sending them scrambling to redo the plan before the 2003-04 year was to begin.

At that time we suggested that then-County Executive Jim Robey convene a blue-ribbon panel to examine ways to improve methodologies employed in projecting enrollements:

"This situation is only the latest example of a problem that has plagued the school system for years," our editorial of June 19, 2003 said. "A remedy for chronically bad projections is long overdue.

"Without reliable enrollment numbers, the Adequate Public Facilities Ordinance is inadequate to its task. Development occurs where it shouldn't, exacerbating school crowding. Conversely, it may shut down development without cause."

These words are as true today as they were then. We urge County Executive Ken Ulman to gather the best minds available from the public and private sectors to take a comprehensive look not at the next round of redistricting but at the way the figures that support these plans are calculated.