INDIANAPOLIS – Indiana’s private school voucher program is exploding in its third year, with more than double the number of student applications over last year.

The voucher program, the broadest in the country, was first approved by Indiana lawmakers for the 2011-12 school year, when 3,919 students immediately signed up to take part. Last year, the program ballooned to 9,324, and more than doubled again for 2013-14 to 20,047 applicants, Indiana Department of Education officials told the Associated Press.

“I think it indicates there is a strong desire for choice by Hoosier families, particularly by those of low and moderate incomes,” Betsy Wiley, president of School Choice Indiana, told the news service.

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“I think it is also clear the vast majority of families and students are being well served in their traditional public schools,” she said. “I believe 20,000 students is great, but we have a million students in school.”

Wiley said it’s unlikely the voucher program will continue to expand at such a rapid rate, mostly because of limited space at private schools. Shortly before the General Assembly approved the program, a study showed 22,000 spaces available at private schools, although Wiley believes some schools have expanded their capacity as the voucher program has grown, the AP reports.

Meanwhile, opponents of private school vouchers, including state superintendent Glenda Ritz, continue to argue that sending students to high-performing private schools hurts public education because state funding follows each child to the school of his or her choice.

When thousands of students choose private schools, public schools no longer have to educate those students, but they don’t receive funding for them, either.

For educators like Ritz and others who subscribe to the union mentality, keeping all the money in public schools is necessary to preserve union teaching jobs. Private schools generally don’t hire union teachers.

But the voucher program  saves taxpayers a great deal of money. The state pays a maximum of $4,700 for elementary school students to attend private schools with a voucher, but the per-pupil funding for children in public schools is significantly more.

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So the kids are getting the education they prefer, and the state is saving money.  How could that possibly be considered a problem?

Ritz is also demonstrating how vouchers are driving public school officials to improve academics to keep students from transferring to private schools. Glitz launched an outreach program for public schools this spring, and is deploying 13 regional coordinators to provide support to help public schools step up their game.

There would be no pressure for public school improvement if there were no voucher program and children without wealthy parents were trapped in public schools.

Eventually Ritz and her cronies will have to admit that this is the best system for everyone involved.