Enrollment in Indiana's school voucher program has more than doubled in the program's second year, the state Department of Education announced Tuesday.

In the current 2012-2013 school year, 9,324 families signed up to participate in the Choice Scholarship Program, up from 3,919 last year.

"We are providing our neediest families options they've never had before, and they're taking advantage of the opportunity to select school stat work best for their children," State Superintendent of Public Instruction Tony Bennett said in a statement. "This socially just policy underscores my belief that all students can and will succeed if we remove senseless barriers that allow achievement gaps and cycles of poverty to persist, especially in our most challenged communities."

The announcement comes as the program, considered the one of the nation's most expansive voucher initiatives, is being challenged in the state's highest court, with oral arguments scheduled for Wednesday. A dozen plaintiffs, including newly elected SPI Glenda Ritz, have filed a lawsuit challenging the its constitutionality and seek a permanent injunction to freeze the program.

Indiana's school voucher program was signed into law last May by Gov. Mitch Daniels, allowing a system in which the state's education department pays for all or part of a child's private education. To be eligible for vouchers, the child must be an Indiana resident and have attended an Indiana public school for the full year prior above the 2nd grade, as well as meeting various other age and family income requirements.

The voucher law led some Hoosier parents to take their students out of private schools and place them in public schools for a year to earn eligibility for the publicly funded program. The nearly 4,000 students that moved to private institutions under the program last year took with them $16 million in state funds.

When the 2011-2012 school year started, the mass exodus of students from public schools who took with them public dollars was met with great controversy. Parents wanted the best education they could get for their kids, public school teachers needed the resources to provide the best education they could for their students.

If voucher students withdraw from private institutions and re-enroll in public schools, the private school must return what's left of the student's funding for the year to the state, but the state doesn't necessarily forward that refund to the student's new public school.

Now, Ritz -- who unexpectedly ousted Bennett as Indiana SPI during the Nov. 6 election -- and her fellow plaintiffs contend that the state constitution forbids using public dollars to support religious institutions. A majority of the 289 private schools accepting vouchers in the states have religious affiliations. Ritz has said that she will rescind her name from the lawsuit to avoid a conflict of interest. From the Post-Tribune:

Specifically, the plaintiffs charge the Indiana Constitution calls for the General Assembly to provide for the education of Indiana children through a “general and uniform system of Common Schools.” Plaintiffs say the law is incompatible with two other provisions in the state constitution that safeguard Indiana citizens’ “freedom of conscience” by ensuring they are not compelled through their taxes to support religious institutions against their consent.

The state contends the General Assembly has the power to provide scholarships and to encourage education “by all suitable means.”

State officials also assert that the program allows parents more flexibility in choosing where their children are educated, expanding horizons for low-income students stuck in troubled schools. State officials say that 81 of voucher program participants come from the state's most impoverished households, while 48 percent of participating students are from minority backgrounds.

"These figures show poverty knows no boundaries and impacts students in every part of the state," Bennett said in his Tuesday statement. "That's why it's important to have statewide policies in place that aim to ensure a wide array of educational options for all families in all communities."

Marion Superior Court Judge Michael Keele upheld the voucher law last fall when it was challenged by denying the plaintiffs' request for a temporary injunction.

"[The law] is religion-neutral and was enacted 'for the benefit' of students, not religious institutions or activities," Keele wrote in his decision. "It permits taxpayer funds to be paid to religious schools only upon the private individual choices of parents."

Proposals for voucher programs are gaining traction across the country amid a contentious education reform movement, though not all states seeing those proposals have embraced the idea.

A Denver judge blocked Colorado's first school voucher program last August, calling it a "substantial disservice to the public interest," and a local school board election was fought among pro- and anti-voucher candidates.

Lousiana's teachers unions, the Louisiana School Boards Association and many school districts have filed lawsuits to block the state's voucher program. The initiative is the linchpin of Republican Gov. Bobby Jindal's bold effort to reform public education in the state and shifts tens of millions of taxpayer dollars from public schools to pay private schools, businesses and tutors to educate students across Louisiana.

The program came under attack for its funneling of funds toward sending children to schools that teach creationism and reject evolution. Several of the religious schools that were set to receive public funds to take in new students from public schools also teach curricula that question the age of the universe, defying scientific evidence and theory and promote religious doctrine that "challenges the lessons central to public school science classrooms."

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