While the Supreme Court listened attentively to oral arguments Wednesday on whether school vouchers pass the constitutional test separating church and state, protesters outside expressed their opinions in more vocal terms.

"If the schools were up to par ... and they were educating children the way they were supposed to be, we wouldn't be here today," said a Cleveland pro-voucher parent who identified herself as Albertina.

"If they rule these vouchers to be constitutional, I know there's going to be a flight from the public school system. And there's going to be even more money taken away from my child's education," said Steve Croom, an anti-voucher Cleveland parent.

The issue before the High Court is whether taxpayer money can be used to help pay tuition at schools outside the traditional public school system.

Carrying signs and donning orange stocking caps, nearly 200 Cleveland area parents and students showed up outside the Supreme Court to shout slogans and show their support for a program that allows 99 percent of students pulled from public schools to use vouchers to attend religious schools. Of those students, 98 percent attend Catholic schools, though outside the High Court Wednesday was a contingent from a Cleveland-area Islamic school.

It's the diversion of public funds to private schools that has opponents particularly upset. Forty-seven of the 50 private schools in Cleveland's voucher program are parochial schools. Opponents say if the Supreme Court gives the Cleveland voucher plan its stamp of approval then "Americans will be forced to support religious indoctrination," in the words of one ardent anti-voucher demonstrator.

Opponents also say if the voucher system is approved by the Supreme Court, it will rob an already cash-strapped public school system of precious resources. Parents of public school students say those classrooms are already hurting, and vouchers will just make things worse.

"It drains away resources from the Cleveland public school system for things like books for students, and there's cases of students not having enough materials to learn properly and to have a proper education in the school system," Croom said.

"My kids have some special needs, and for me it's a daily struggle to get them the extra attention that they need, and I feel that if there are budget problems now, if money is being taken away from public schools, those problems will get worse," said Jacqueline Veldhuis, a parent who came from Maryland to protest outside the court.

But among the nearly 400 people in attendance Wednesday, proponents outnumbered opponents by a three to one ratio. And their message, carried by microphones and organized speakers, could be heard across the plaza even after the anti-voucher crowd called it a day.

Those in the crowd of supporters said their children deserve the chance to go to a good school. They said the public school system has failed their children and parents shouldn't be turned away from a good private school just because they can't afford the tuition on their own.

"The rooms aren't as crowded and the teachers, they explain things to us," said Tenise Edwards, a private school student who benefited from the voucher program.

"It's an overcrowded classroom, safety issues, those type of issues that are disturbing, and a child shouldn't have to worry about who has a knife today, or who has a gun today, or am I going to eat some of the ceiling falling from the ceiling into my food, you know, those are health issues," said Cleveland parent Shirley Edwards.

Fox News' Todd Visioli contributed to this report.