The numbers are not adding up for South Bay school districts as they struggle every day to find out how to make up for lost revenues caused by families moving out of the area due to the high cost of living.

As classes let out in the Franklin-McKinley School District in San Jose, administrators remained hard at work. Lately, they’ve been doing a lot of subtraction.

"It's one of those things that keeps me up at night," district Superintendent Juan Cruz said. "Because we know that the reduction in funding means reduction in services."

The reduction in funding is caused by declining enrollment. For every 100 students that move out of the area, it means a $1 million loss in state funding for the district.

Across town, the Oak Grove School District lost 425 students last year.

"It’s a struggle for us," parent Eilene Cruz said. "Our my family is struggling with the cost of living and thoughts of having to move out of town and not be in the community we grew up in."

School officials say another reason for enrollment decline is the recession of 2008. That’s when the birth rate fell and hasn’t recovered.

"It’s been pretty rough," parent David Gomez said. "I’m a single dad raising two daughters so everything is really expensive."

So, instead of focusing solely on curriculum, budgets occupy a large part of the minds of superintendents.

"We try to make sure we don’t let that be a distraction at the classroom level," Superintendent Cruz said. "But it's hard to not be worried about the future of the district."

Franklin-McKinley is undergoing an 18-month budget review to see how to keep the district sustainable. And closing schools in the next few years has not been ruled out.

No schools will close in the Franklin-McKinley district until after that 18-month review is complete. But the option has to remain on the table, Cruz says, because costs continue to go up and revenue does not.