Between 2010 and 2015, Connecticut's population of school-aged children decreased by 3.46 percent, the sixth highest rate in the nation, according to data from the U.S. Census.

By 2025, the student population is projected to decline by nearly 10 percent to 631,241 students, according to the Connecticut State Data Center.

Experts link decreasing student enrollment to a variety of factors, from a decline in the state’s birth rate, as people have fewer children and have them later in life, to people leaving the state for job opportunities.

The Waterford school district has seen a smaller decrease in its population than some southeastern Connecticut towns, but the issue is still on school officials’ minds.

“Like most towns in Connecticut, it is declining a little,” said Thomas W. Giard, Waterford’s school superintendent. But, he said, “we’re not seeing a mass exodus.”

In the district’s three elementary schools, the number of students is expected to shrink by about 28 students between this year and next year, from 1,023 to about 995.

About 47 fewer students will walk into Clark Lane Middle School next September as they did this year.

Only Waterford High School will see a higher number of students, an increase of 22 students between this and next year.

“This is obviously a very desirable school district to move to,” Giard said. “I think people see the investment that the town has made ... over the last eight years or so.”

Many of the forces that control school enrollment over the years, like the regional birth rate, are beyond the district’s control, he said, but “my understanding is it’s a fairly stable population.”

But relative to the district’s history, numbers going down rather than up, is a recent phenomenon. The district’s numbers started going down in the early 2000s after five years of 13 percent growth, according to state statistics.

While the Waterford Board of Education considered rebuilding the Oswegatchie, Quaker Hill and Great Neck elementary schools and closing two other schools in 2004, it commissioned a study on the district’s enrollment future.

Hyung C. Chung, an Orange consultant, predicted in a 2002 study and a 2004 update that enrollment at the town’s elementary schools would drop by nearly 5 percent in the following 10 years.

The district decided to close the Cohanzie and Southwest elementary schools, and rebuilt Clark Lane and Waterford High School, Giard said.

That means the amount of space in Waterford schools is appropriate for the number of students, he said.

“We have pretty good data,” he said. “The sizes of the buildings that were built reflected those projections.”

But to maintain ideal class sizes, lower enrollment has meant downsizing elsewhere.

“We’re definitely down staff,” Giard said.

Since the 2009-10 school year, the district has dropped a dozen staff positions.

To keep students from leaving the district, officials have organized programs aimed at pushing Clark Lane students into Waterford High School. More recently, Giard said the district has promoted it’s coding and computer science programs, which now start as early as kindergarten.

“People are looking at Waterford as providing a quality education,” Giard said. “I think people remain positive about the education their child gets here.”

But enrollment is a constant factor for the district’s allocation of resources. The district has started to work with the regional nonprofit LEARN and the New London school district to share things like teacher training or adult education programming.

“Each year we start with a fresh look at the budget,” Giard said. “It’s really starting from scratch and evaluating what we need.”

m.shanahan@theday.com