Gov. Mitch Daniels signed the nation's broadest private school voucher system into law Thursday, part of sweeping education reforms he championed that won approval in the Indiana Legislature.Lawmakers and supporters joined Daniels at a Statehouse ceremony where he signed the voucher bill and another proposal aimed at expanding charter schools, which are public schools free of many state regulations.The controversial voucher program would allow even middle-class families to use taxpayer money to send their children to private and religious schools.Unlike other systems that are limited to lower-income households, children with special needs or those in failing schools, Indiana's voucher program will be open to a much larger pool of students, including those already in excellent schools.Families will have to meet certain income limits to qualify, with families of four making up to about $60,000 a year getting some type of scholarship.Advocates of the voucher program claim Indiana will become a model for other states considering education reform."All of our children, regardless of whether they go to school, are our public," said Tony Bennett, Indiana superintendent of public instruction. "These children are part of our public. It's imperative we make the right decisions for them."Opponents claim the voucher program will hurt public schools by taking money and students away from them and that it blurs the line between separation of church and state.The voucher proposal was a key reason behind a five-week boycott of the Legislature by House Democrats, who returned to the Statehouse from Illinois only after winning concessions on the voucher bill and other proposals.Republicans around the country are pushing to expand voucher programs after the GOP made big gains in the 2010 elections. But Indiana's proposal differs from existing programs.Other voucher systems across the country are limited to lower-income households, children with special needs or those in failing schools.Indiana's program would be open to a much larger pool of students, including those already in excellent schools. Indiana's program will be limited to just 7,500 students for the first year and 15,000 in the second, a fraction of the state's about 1 million students. But within three years, there will be no limit on the number of children who could enroll.The education proposals enacted into law Thursday are a major part of Daniels' aggressive education agenda. The GOP-ruled General Assembly approved all of the governor's proposals, handing him big legislative victories as he considers whether to run for president.The vouchers themselves do not carry any additional expense for the state because they mainly transfer money between schools.The actual value of the vouchers is based on a sliding scale and is less than the amount of tax money a public school would have received for that student. In the case of students in grades 1 through 8, the maximum value would be $4,500.But the bill includes a tax deduction of $1,000 for each child in a private school or home school. That will translate into a revenue loss of more than $3 million, according to the nonpartisan Legislative Services Agency.