An enrollment drop in 10 of 14 Snohomish County districts has school leaders wondering where the students have gone.

Enrollment declined across the county by more than 300 students, slipping to 107,445, according to head counts taken by the districts last month.

What’s most perplexing is the dip is occurring while hundreds of new homes across the county are being built and moved into.

“We are all sort of in the same arena of scratching our heads,” said Arlene Hulten, a Lake Stevens School District spokeswoman.

The districts expect enrollment will rebound as families with school-age children move into the new homes.

For now, it may be that some families are passing up Snohomish County on their way to cheaper housing in surrounding areas.

“The general trend is that there is small growth in Whatcom and parts of Skagit counties and there is a reduction in San Juan and Snohomish counties,” said Jerry Jenkins, director of the Northwest Educational Service District. “I would suppose that the likely cause would be housing costs and that young people with families can stretch their dollars further.”

Other factors are also suspected, including a slower birth rate in the county five years ago. Ten of 14 districts had a smaller kindergarten classes than a year ago.

Statistics kept by the U.S. Census Bureau showed a drop of more than 1,500 school-aged children between the ages of 5 and 9 in Snohomish County between the years 2000 and 2006.

More students also are choosing online schools instead of the traditional classroom.

The Edmonds School District surveyed families earlier this year and found more than 40 students who said they were planning to enroll in an online school this fall. Edmonds is now considering starting its own online program.

“That has happened a little bit,” said Nathan Olson, a spokesman for the state Office of Superintendent of Public Instruction. “In terms of a percentage, it’s probably not much, but it is happening.”

The state does not have statewide enrollment numbers for fall.

Projecting enrollment accurately is key for each district as more than 70 percent of its budget is based on the number of students in classrooms. Districts receive more than $5,000 from the state for each full-time student.

Housing, birth rates, population trends and job losses all figure into projections.

The Monroe School District was one of two districts to see enrollment growth in large part because of its new online school for freshmen and sophomores. The school is called Washington Virtual Academy. October enrollment was 264 for the virtual school and the plan is to add a grade each year until it is a ninth- through 12th-grade school. Students have enrolled from across the state with most from outside of the county, said Rosemary O’Neil, a school district spokeswoman.

The Monroe district also added 95 more students to its home-school program this fall, increasing enrollment there to 727.

The district grew from 6,795 in 2006 to 7,174 in 2007, an increase of 379 students.

“The only growth was in the alternative programs,” O’Neil said.

Similarly, the Marysville School District saw a slight increase in enrollment only because of a fast-growing online program that also attracts most of its students from outside the county.

“It was done out of a concern for recapturing some of the students who were dropping out,” said Larry Nyland, the district’s superintendent.

Everett School District, which opened a new elementary school in its fast-growing south end, saw enrollment increase since 2006.

In most districts, enrollment was flat with slight losses.

In Lakewood, for instance, the October head count was exactly the same as last year.

The Edmonds School District experienced the most dramatic loss, dipping from 20,725 to 20,352.

The loss of students can be costly. Edmonds estimates it lost about $1 million in state revenues because of declining enrollment. It won’t fill some vacant positions but won’t have to make layoffs either, according to a district memo.

Reporter Eric Stevick: 425-339-3446 or e-mail stevick@heraldnet.com.

Enrollment for area school districts

School district20062007

Arlington5,5735,448

Darrington568537

Edmonds20,72520,352

Everett18,53918,573

Granite Falls2,3222,314

Index3026

Lake Stevens7,6007,582

Lakewood2,5312,531

Marysville11,80311,827

Monroe6,7957,174

Mukilteo14,23414,203

Snohomish9,4479,425

Stanwood5,3655,309

Sultan2,2232,144