ATLANTA — Georgia was the first state in the nation to allow Bible classes in public schools, but the number of districts offering the classes has dwindled to just a handful as budgets tighten.

Superintendents say interest has waned in the once-controversial classes and schools don’t have the money to pay for courses with only a few students enrolled. What’s more, budget cuts mean it now takes more students to fill up a class than ever before — some classes need more than 25 enrolled before they are considered affordable.

“We’re not going to utilize a teacher for a whole period with 10 to 15 students. In the past, we may have considered that, but with the economy being the way it is, we just can’t afford to do that,” said Columbia County schools Superintendent Charles Nagle, who has cut the Bible classes from three to one in his tiny district.

Just 21 middle and high schools in 16 districts — a fraction of the 180 school districts in the state — offered the voluntary classes last school year, according to the latest data available. That’s compared to 48 districts offering the classes four years ago.

Some of that drop-off is due to students having little time in their class schedules for elective courses because they have to repeat the state’s new, tougher math courses or need an Advanced Placement class to help with college admissions, educators said.

“We’re seeing a lot of elective classes, not just Bible, close because there aren’t enough students taking the courses because they’re repeating math several times,” said state schools Superintendent John Barge, who worked in Barrow County schools before he was elected.

A Georgia law supporting the voluntary Bible courses was passed in 2006 with overwhelming support from both Republicans and Democrats at the statehouse, and the classes were first offered during the 2007-08 school year after the state school board selected a curriculum.

Critics worried that the law would lead to students being force-fed religion and open schools to lawsuits. Under the law, the classes must be taught “in an objective and non-devotional manner with no attempt made to indoctrinate students.”

Senate President Pro Tem Tommie Williams, a Republican from Lyons, said he hopes cash-strapped schools can begin offering Bible classes online to help cut down on costs but keep the courses available. Williams, the most powerful state senator in Georgia, was a backer of the law when it passed in 2006.

“It is unfortunate that schools are not able to offer these classes, but when times are tough local and state government have to make decisions based on the realities of their budgets, in the same way Georgia families and business have had to do with their own budgets,” Williams said.

Since 2006, Texas, Tennessee, South Carolina and Oklahoma have followed Georgia and passed similar laws.

Other states like Alabama have stopped short of adopting laws but still provide the curriculum in schools. Hundreds of public schools across the country offer voluntary Bible courses to students even though their state doesn’t have a law specifically addressing the issue.

According to the Greensboro, N.C.-based National Council on Bible Curriculum in Public Schools, which provides teaching materials to schools, nearly 600 school districts in 38 states are teaching Bible classes. Another group, the Virginia-based Bible Literacy Project, has sold its textbook to more than 500 schools in 43 states.

The Bible already is incorporated into comparative religion and other public school classes in many states, but those classes are funded by the local districts, not with money from state government.

In Georgia, the school systems offering Bible classes tend to be in more rural parts of the state with low student enrollment. For example, Gordon County in northwest Georgia has just two high schools, neither of which offered the Bible electives last year.

“When we first started offering it was new and kids had interest in taking the class,” Gordon County Superintendent Bill McCowan said. “We’ve expanded our elective offerings in social studies and history to include more Advanced Placement coursework. There’s only so much student head count to go around.”

Georgia districts offering the classes last year ranged from Gordon County to Effingham County along the southern coast, according to state records. Richmond County in east Georgia was the largest district to offer the classes last year — at four high schools.

Some parents say they wish their districts had the Bible classes because children need to know how influential the text has been on literature and pop culture.

“We need to bring that back into the schools because kids now, the new generation, just has so many issues,” said Wendy Labat, whose son is an eighth-grader in Clayton County, which has never offered the Bible electives. “Whether you believe in God or not, it’s still the word of God and kids need to have that experience.”