SOUTH BEND, Ind. — Struggling Indiana public school districts are buying billboard space, airing radio ads, and even sending principals door to door in an unusual marketing campaign aimed at persuading parents not to move their children to private schools as the nation’s largest voucher program doubles in size.
The promotional efforts are an attempt to prevent the kind of student exodus that administrators have long feared might result from allowing students to attend private schools using public money.
If a large number of families abandon local districts, millions of dollars could be drained from the state’s public education system.
‘‘If we don’t tell people the great things that are happening in our schools, no one else will, especially not now,’’ said Renee Albright, a teacher in Fort Wayne. ‘‘There are private enterprises that stand to benefit if they can portray us as failed schools.’’
The Indiana voucher program, passed by the Legislature in 2011, is the biggest test yet of an idea sought for years by conservative Republicans, who say it offers families more choices and gives public schools greater incentive to improve.
But school officials worry about the potential loss of thousands of students, especially those from the middle class, and the state money that comes with them.
Unlike voucher programs in other states that are limited to poor families and failing school districts, the Indiana subsidies are open to a much broader range of people, including parents with a household income of up to nearly $64,000 for a family of four.
The median income for an Indiana family of four was about $67,000 in 2010, making many of the state’s nearly 1 million public school students eligible for vouchers.
Last year, the effect of the new vouchers was limited because the law passed just four months before the start of school, and many parents were still unfamiliar with the program. But this year, more than 8,000 students have already applied for vouchers, and there is room for up to 15,000. The number of participants could grow even more next year, when the ceiling on the number of vouchers is eliminated.
Leaders of poor urban schools, which suffered the most defections last year, are especially worried. A district loses $5,300 to $8,400 for each student who leaves.
After 113 of its students departed for private schools last year, the Evansville Vanderburgh district spent $5,700 to erect two billboards and place ads at bus stops to promote the district’s theme of ‘‘Bringing Learning to Life.’’
In Fort Wayne, public schools lost 392 students to vouchers last year, the most in the state. That cost the district more than $2.6 million in state aid and led officials to cut 10 art, music, and physical education teaching positions at elementary schools.
Principals have gone door to door in neighborhoods to make their case for the city’s public schools, promoting improved test scores and a 90 percent graduation rate. The district has spent $32,000 on a marketing campaign titled ‘‘Their stories. Your school. Get back to school’’ at Fort Wayne Community Schools.
Oscar Dowdell-Underwood Jr., headmaster of Cornerstone Christian College Preparatory Day and High School in Fort Wayne, isn’t sympathetic. He said the voucher program forces public schools to realize that every student matters.
His school added 94 voucher students last year, the second most in the state, which helped boost enrollment from 26 students in 2010-2011 to 129. This fall, Cornerstone will have an overall enrollment of 158, including 115 voucher students.
No one knows yet whether the marketing is paying off. Indiana schools won’t count students until mid-September.
Philip and Cheresa Covington have not been swayed. They pulled their seventh-grader out of public school because his language-immersion program promised more than it delivered.
This year, their son will use a voucher worth $4,500 at a small private school in downtown Indianapolis called the Todd Academy. Annual tuition is $9,850.