THE HOTTEST TOPIC in education right now is vouchers, thanks to state Senate Bill 1, now being debated around the state.

The bill is being touted as a single solution to many problems: the problem of failing schools; the problem of struggling parochial schools; the problem of poor parents who need a chance to level the educational playing field for their children, and for some proponents, even the problem of a racially imbalanced education system that harms poor black children.

SB 1 might address some of these things, but it is also would cause more problems than it would solve.

It ends up becoming an expensive entitlement.

In the first year, the bill would allow parents whose family incomes are up to 130 percent of the poverty line and who have children in failing schools to use the state's per-pupil funding - in Philadelphia, that's $7,100 - toward tuition in a nonpublic school. In Philadelphia, in particular, that could help right some racial inequities that find too many poor black kids in failing schools.

But by the third year, all children in that income bracket would be eligible for a voucher, even those already in private schools. That may help many poor families, but it doesn't help reform public schools. The Senate Democratic Appropriations Committee figures that this bill could end up costing a billion dollars a year.

It ends up taking public money away from public schools.

By the second year of the program, each voucher issued will reduce the funding for the school district from which the child is leaving. So if only 10 percent of the 51,000 eligible Philadelphia students get a voucher, the school district will lose $36 million of its state funding, as well as federal funding that is based on per-pupil subsidies. That means not only that failing schools will get further slammed but also that all children left behind in district schools will have less.

In fact, the basic math in the voucher equation is faulty at best, and a fallacy at worst. Consider: A classroom that loses four students to nonpublic schools still has the same fixed costs as before - personnel, heating, building maintenance, etc. - but now it has less money to cover those costs. Sure, the district's administration could get leaner and meaner, to a point. In reality, though, the only thing getting leaner and meaner is education itself. Which makes the idea that public schools would become more competitive -an argument for the bill - a fantasy.

Oh, and those vouchers for the 50,000 or so students already in private and religious schools? That money will be underwritten by taxpayers.

It represents a massive transfer of public money into the private and religious sector - with no strings attached.

The private and parochial schools don't have to follow state regulations. They don't have to test for performance, open their books, or even be accredited. They can use their own guidelines for accepting children -which means they don't have to take troubled students, disabled students, struggling children, or children with special needs. Many voucher opponents, in fact, fear that vouchers will skim the most promising students, and leave behind those more difficult to teach. With less money to do it. Remind us, again, how these schools will be become "more competitive."

Although the concerns about the separation of church and state are real, the Supreme Court upheld the legality of vouchers. But that still doesn't make us comfortable with transferring hundreds of millions of public dollars into private systems that don't have to account for that money.

It assumes that all private and parochial schools are better than all public schools.

Parochial and private schools are key parts of the education landscape, and many of them produce exceptional results. (The Archdiocese of Philadelphia says that 99 percent of its secondary students graduated last year.)

But two studies in particular -one from the Center on Educational Policy and another from the U.S. Department of Education - showed that nonpublic-school students from low-income backgrounds perform about the same in reading and math as their counterparts in public schools - and in some cases, not as well.

Public-education dollars belong in public schools.

In the past few years, the state and the feds have given more money to public schools. In Philadelphia, those dollars have led to higher achievement levels. Those dollars have also led to wider choices for parents, with 74 charter schools in this city alone. While we commend the sponsors of SB 1 for trying to create more options to help more children, the bottom line is that public money belongs in public schools.