Just two years ago, Aurora schools faced overcrowding, with almost all of them more than 90 percent full. Now the district is facing a different problem, with projections showing that only one of the 27 district elementary schools will be close to capacity next year.

The changes happened so fast that Brett Johnson, Aurora Public Schools’ chief financial officer, acknowledged that “we haven’t had time to discuss what do with all this underutilized space.”

There are several factors driving the decline: gentrification and higher costs of living, causing families to relocate, and a growing number of students enrolling in charter schools, which in Aurora usually find and pay for their own facilities. This school year, the district has 31,263 students, in grades kindergarten through 12th grade, down from 34,037 two years ago.

Falling enrollment is costing the district about $21 million this year, Johnson said, and if the trend continues, the cost will go up by $3.1 million with each passing year.

“Everything has a cost,” Johnson said.

As the Aurora school board considers a new plan for the future of the district’s programs and facilities, it may soon consider shuttering schools. At this point, no schools have been identified for possible closure.

Superintendent Rico Munn told the board that current district policy directs staff to evaluate the best use for school buildings as “neighborhood schools operating at full capacity.” That means there’s no room currently to suggest using a school building for other purposes.

“That’s what we’re directed to use the buildings for,” Munn said. “Of course we know that our schools can end up serving lots of different purposes in our communities and lots of different things which we want to acknowledge and we are not ignoring that.”

But he said there are “very practical and logistic things” that district leaders must consider, given the rising costs of keeping schools open while operating well below capacity.

The problem, as Johnson put it, is two-fold. A big building that is only used by about half the students it’s designed to accommodate costs more per student because costs for maintaining a building, paying a principal, or keeping the electricity running, don’t decrease with fewer students.

If a roof needs to be replaced, “you don’t build half of a roof,” Johnson said.

The second part of the costs are related to the number of students in schools. Schools with few students always cost more per student since the state provides money to districts, and districts to schools, based on how many students are enrolled. Fewer students means less money.

Johnson’s analysis presented to the board estimated that an elementary school of about 225 students costs about $8,300 per student to run — about $2,000 more per student than a school of about 500 students.

A school could have both problems, or only one. A school that has 300 students could be 100 percent full in its building, meaning it may still be efficient to operate when compared to a school serving 500 students, but in a building designed for 1,000.

While all but one of the 27 district-run elementary schools in Aurora are expected to lose several students next school year, a district analysis found 10 will cost more per student, taking into account both having fewer students and also being under capacity.

Chalkbeat looked at the district’s enrollment projections and found, for example, that Aurora Century Elementary is expected to have only about 207 students next year, which would put the school at 42 percent of its capacity. Dartmouth and Park Lane elementary schools are in similar situations both hovering around 50 percent full, and each expected to have fewer than 300 students next year.

Dartmouth is less than two miles away from Aurora Century. Park Lane is in northwest Aurora where most new charter schools are opening and where enrollment declines have been some of the steepest.

School board member Dan Jorgensen, asked the district to consider whether, in some cases, the value of a school for a community might be worth the district’s extra costs.

Education research has shown that schools with more students of color are more likely to be shut down. Research on the impact of such closures shows that students can benefit if there are better schools for them to attend. But when there’s a constant churn of students switching to similarly performing schools, students can end up worse off academically.

Board president Marques Ivey was concerned about whether or not communities around the district are aware of the possibility of school closures.

Superintendent Munn pointed out that as part of the district’s “Blueprint” work, a process to create a plan for how schools should function in the future, which has included surveys and community meetings, has included discussions about possible closing schools. Earlier this year, the school board was presented with several scenarios of possible models for moving forward, and all included closing or repurposing schools. Board members have expressed some hesitation about selecting a one-size-fits-all approach districtwide. A decision could be made next month.

While waiting for the board’s long-term guidance, Johnson said that district officials are looking for shorter-term ways to cut costs as they build next school year’s budget.