The number of Indiana students receiving vouchers increased by almost half during the 2014-2015 school year.
The Center for Education Reform ranked Indiana's voucher program as the best in the country.
A proposal to let voucher-accepting private schools opt out of the state's ISTEP+ test fizzled in committee Wednesday.
Voucher proponents say Indiana's maximum award amount is too low to continue attracting new students at the current pace.
D or F rated private schools had, on average, twice as many voucher-recipient students as the A schools.
Indiana awarded 19,809 private school tuition vouchers for the 2013-14 school year, up from 9,139 last year and 3,911 two years ago.
Roughly 40,000 low-income 4-year-olds would qualify for preschool vouchers each year under the measure Gov. Mike Pence is proposing.
The law increases the maximum amount of a voucher, and guarantees eligibility to siblings of voucher students.
But the expansion isn’t nearly as broad as many, including Pence, wanted.
Legislators plan to vote in early evening on a new state budget which calls for a five-percent income tax cut, phased in over the next four years.