Public charter schools have grown exponentially in Pennsylvania because parents want educational choices that best suit their children.

But state law has not kept up with that growth, allowing the growth, as well, of vast funding disparities and gaps in accountability.

A comprehensive bill sponsored by Republican state Rep. Mike Fleck, with broad bipartisan support, would correct many of the funding disparities and boost accountability.

According to the state Department of Education, there are 167 charter schools across the commonwealth, with total enrollment of more than 105,000 students. Of those schools, 154 are physical locations, with more than 72,700 students, and 13 are "cyber" charter schools that operate over the Internet, with more than 32,300 students.

Tuition is paid to charter schools by each student's home school district. The payment is based on each district's own cost-per-student, rather than on the charter school's actual costs. An analysis by Auditor General Jack Wagner has found that tuitions at a single Internet charter school vary widely, from about $4,478 to $16,915.

Mr. Fleck's bill would alter the tuition formula for charter schools and hold them to some of the same constraints faced by the public schools from which they derive their funding.

For purposes of determining charter school tuition, for example, school districts would be able to deduct from their per-student cost the amount that they pay into teachers' pensions. That alone would save local districts $510 million over four years, according to Rep. James D. Roebuck, the ranking Democrat on the House Education Committee, beginning with $45.8 million for 2012-2013.

Districts also would be able to deduct their costs for athletics and other non-instructional services. Districts, quite rightly, are required by law to allow charter school students to participate in district athletic programs, whereas most charter schools do not operate athletic programs.

The bill also would preclude charter schools from holding reserve funds beyond the 12 percent limit imposed on school districts. Mr. Wagner's analysis found that more than half of charter schools had "unassigned" reserves greater than 12 percent, ranging up to 95 percent.

At the end of each school year, the Department of Education would be required to conduct charter school audits to determine the actual cost of education at each, which would have to be reconciled with tuition payments. Overpayments would be returned to school districts.

Charter schools are public schools. Mr. Fleck's bill would hold them to the same financial standards while enabling traditional public schools to better deal with budget cuts. Lawmakers and Gov. Tom Corbett should implement it for the 2012-2013 school year.