Each Fairfax County elementary school will be required to carry at least one phonics-based reading textbook series from kindergarten through second grade, the county School Board decided last night.

The action came weeks after schools placed orders for new reading books. Board members said funding for the additional texts, at an estimated cost of $250,000, will come from the school district's budget and not from individual schools.

Last night's action followed news last week that more than two dozen of the county's 132 elementary schools declined to select either of two new textbook series that place a strong emphasis on phonics. Board members were especially upset that several of the schools that chose not to use a heavily phonics-based series had already been targeted as low-performing and most likely to benefit from a strong phonics program.

The board adopted four new series of elementary reading books in December, including the two that rely most heavily on phonics. That vote marked the first change in elementary reading texts in 12 years. Board members said the selections illustrated the county's commitment to strong phonics instruction and an end to the so-called "reading wars" that pitted phonics against the so-called whole-language approach.

Each elementary school was then allowed to choose any two of the four series, and many board members assumed that schools would choose at least one of the phonics-based books.

Most schools chose "Signatures for Young Children" by Harcourt Brace & Co., which has a strong phonics component but is viewed by many educators as taking a more balanced approach to teaching reading. Some schools chose "Collections for Young Scholars" by Open Court, the series most favored by those who believe systematic, explicit phonics instruction is the best way to teach children to read. And 15 schools selected the Open Court and Harcourt Brace series.

But 26 schools decided to take neither, leading to the board's action last night. For decades, debates over how children should be taught to read have been among the most contentious in public education. The debate has revolved around phonics--in which children learn to read by sounding out the letters in a word--and "whole language," which emphasizes exposing children to literature and getting them to recognize words from the context of a story or the accompanying illustrations.

Research has shown that a blended approach, combining elements of both methods, often works best for most children. But researchers also have found that there are some children who will learn effectively only through phonics. Board members said they wanted to make sure that all schools had at least one of the strong phonics series to help those children.

In other business, the board agreed that a sex education video shown to fifth-grade girls should be edited to exclude a scene on boys' sexual development. Some parents had complained that a scene in the video "The New Improved Me: Understanding Body Changes" was inappropriate for viewing by girls.