The Legislature's independent budget office estimates that expanding a school voucher program to all Arizona schoolchildren over the next four years could cost more than $24 million.
That's because more public school students are likely to take state cash for private schools and children who never went to public schools would qualify.'
Republican Sen. Debbie Lesko is pushing the proposal to expand what started several years ago as a small program. It has since been revised to cover about 186,000 of 1.1 million public school students.
A cap that expires after 2019 limits current enrollment to about 5,500 students.
Lesko said Wednesday she hadn't studied the Joint Legislative Budget Analyst report. She has said expansion saves money.
Democratic Sen. Martin Quezada says the cost estimates are likely conservative.