HARRISBURG - Two years after the Legislature made the state responsible for approving Internet-based charter schools, the way that these "cyberschools" are funded remains a sore spot for many school districts, which must foot the bill.

In recent weeks, the state has sent out hundreds of warning letters about overdue cyberschool tuition payments, said Dan Felix, the Education Department's charter-schools teams leader.

"We wish school districts would pay the cyberschools," Felix said, "but this is their form of denial."

If schools refuse to pay, the Education Department simply deducts the amount of unpaid tuition from their state aid.

The Legislature gave the state oversight of cyberschools at the request of school districts, which did not want the responsibility.

Charter schools, including ones providing Internet-based distance learning, are run by independent entities subject to less stringent state regulation.

Funding, however, still comes from students' home school districts. Districts must pay full tuition for any resident student who enrolls in a cyberschool - regardless of where it is based - using a combination of state and local tax money.

"We still need to find a way where school districts are not a major source of funding," ideally with the state picking up at least half the cost, said Tim Allwein, a spokesman for the Pennsylvania School Boards Association.

The Mars Area School District in Butler County is among districts that have decided not to pay any cyberschool tuition bills as a form of protest. Superintendent William Pettigrew Jr. said he questions whether the per-pupil tuition formula reflects the cyberschools' actual instructional cost.

"If the Department of Education and the Legislature want these schools, they should be paying the tuition for those students," Pettigrew said.

Before the Legislature put cyberschools under state control, eight of them began operating in Pennsylvania after obtaining the approval of the local school districts that sponsored them.

Of those schools, one was forced to close last year after its charter was revoked. Both the Education Department and the state courts upheld a suburban Philadelphia school district's decision to shut down the Einstein Academy Charter School because of a multitude of problems, from improper financial management to a failure to provide a proper special-education program.

Einstein officials had blamed the problems on school districts that withheld tuition payments and challenged the school's legality in court.

The first cyberschool to open under the new approval process has just completed its first year. Three others were approved earlier this year to enroll students starting this fall.

Organizers behind the newest cyberschools say the application process requires intense attention to detail. Applicants must prove, among other things, that sufficient support exists for the school among students, parents and teachers and that its curriculum conforms to state academic standards.

In September, Commonwealth Connections Academy became the first state-approved cyberschool to open in Pennsylvania. The Harrisburg-based school enrolls more than 400 students in grades kindergarten through eight.

"They legitimately put us through the hoops, and we were glad to accommodate them," said Mickey Revenaugh, vice president of state relations for Connections Academy, a Baltimore company that manages the school.

Even unsuccessful applicants agree that their bids to set up shop in cyberspace deserve stricter scrutiny.

"I really believe that the state is doing it for the interests of the children," said Carolyn Knapp of Ulster, Bradford County. Her application for a cyberschool devoted to agriculture was rejected in November for reasons such as failing to provide a financial plan for the school.

Cyberschools cater to a wide range of youngsters, from advanced students who want to progress at a faster pace to those who are homebound because of serious illness.