KANSAS CITY, Mo. -- Missouri lawmakers are trying to prevent an influx of students transferring out of failing schools after the state Supreme Court partially sided with a group of St. Louis parents suing to force unaccredited districts to pick up the tab to send students to accredited schools.

Critics say the lawsuit could overcrowd suburban classrooms and bankrupt the struggling school systems in St. Louis and nearby Riverview Gardens, the state's two unaccredited districts.

Ten other districts, including Kansas City, are provisionally accredited, which means the lawsuit could potentially affect them if they become unaccredited.

Parents say they need an alternative to bad schools or paying for good ones.

"Countless families leave their residence in the city of St. Louis once their children become school age because the school system is not acceptable," said Jane Turner, a plaintiff.

Turner was among parents paying to transfer their children to the suburban Clayton district when the St. Louis district lost its accreditation in 2007 following years of low test scores and other problems. When Clayton refused to send Turner's tuition bill to St. Louis, she and three other parents sued.

The Missouri Supreme Court agreed last summer that students living in unaccredited districts are owed free transfers and that accredited schools must take the students.

The court sent the case back to a local court to work out the details.

While the litigation continues, accredited districts are still limiting admission to students from the two unaccredited districts and legislators are working on what they call a "Turner fix." Legislative proposals include excluding students from transferring if they hadn't previously been attending district schools, addressing fears that students from private and parochial schools also would transfer.

Elkin L. Kistner, an attorney for the plaintiffs, said parents are simply asking that the law be enforced. Kistner said school districts should have gone to lawmakers years ago if they wanted the law changed.

"They are holding hands and singing in unison a song of falsity, and everyone on the government's side complains about the parade of horribles," Kistner said. "They are preventing any traction from occurring as far as the Supreme Court ruling."

Demand for transfers promises to be high.

More than 6,000 students from St. Louis are attending suburban school districts and about 170 county students are attending magnet schools in the city through a voluntary transfer program that was the result of a school desegregation case. But only minority students qualify for suburban transfers and space is limited.

Usually, 3,000 city students apply, and this school year there were only slots for about 600 new transfer students, said David Glaser, CEO of the Voluntary Interdistrict Transfer Program.

If unlimited transfers are allowed, the education everyone receives could suffer, Glaser argued.

"There literally isn't space," he said. "What do you do? Take a class size of 20 and make it 40."

Plus, the suburban St. Louis districts said they suffered previously when they took in dozens of students from the now-defunct Wellston School District after it lost its accreditation in 2003.

By 2006, the state decided to take action as Wellston fell behind on tuition bills that were totaling about $1 million a year. The state created "interim accreditation" to spare the district the additional expense of future student transfers. Clayton and several of the other districts didn't get the money they were owed for the transfer students until June 2010, as the 500-student Wellston district shut down.

"Countywide, there were a lot of people who were really not happy with how the Wellston situation worked out," said Chris Tennill, a spokesman for the 2,500-student Clayton district.

Tennill said Clayton wants the issue settled and has filed a counterclaim seeking to force the plaintiff parents to pay this year's tuition -- an effort designed to ensure the three remaining plaintiff parents don't drop out of the litigation as their legal expenses mount and their children graduate.

"One of the last things we really want to see happen is to lose all the plaintiffs in this lawsuit and not be able to litigate this and address the bigger issue of the impossibility of complying with the state decision," Tennill said.