THERE ARE a few bright spots in the revised Senate Bill 1 that would create a school-voucher program in Pennsylvania. Vouchers give money that would otherwise go to public-school systems directly to students to apply toward tuition in nonpublic schools.

Unfortunately, those spots are only bright in comparison with the dimness of the overall picture.

The brightest spot is that the new voucher bill - which passed yesterday in the Senate and now goes to the House - amends a far more ambitious, extensive and costly program that came out earlier this year from the Senate Education Committee. That bill would have ultimately given vouchers to all students in certain income brackets, even if they are already attending private school, a plan that some estimate would have cost $1 billion a year.

The new bill would give full vouchers - $7,100 for Philadelphians - to families with incomes of up to 185 percent of the poverty limit, and more limited vouchers for incomes 130-185 percent of poverty; students must also live in the boundary of a failing school. It includes current private-school students whose family incomes qualify.

The goal of vouchers - and a notable one at that - is to rectify that poor kids in failing schools are penalized for living in the wrong ZIP code, by giving them the option of attending a private or parochial school. Obviously, that's a hard mission to argue against, but the reality is vouchers end up penalizing far more students: those left behind in the public schools. Those schools are likely to get even worse since, after the first year of vouchers, they will be losing every dollar that follows a voucher student out of the school.

The money for vouchers comes out of the student's school-district per-pupil allocation; more than 50,000 students in Philadelphia are eligible. If only 10 percent of the families take advantage of vouchers, that reduces the school-district budget by $30 million. That's on top of budget cuts already made this year.

Nonvoucher public-school students will be left behind in public schools now operating with even less money. They will be in classrooms with more students, fewer teachers and fewer programs. In effect, a few students get out of failing schools, leaving behind schools that will continue to fail, at an even faster rate.

How does this make sense?

It doesn't. But another bright spot in the bill - which also would bring a few welcome changes to charter schools - could provide an effective compromise. The Educational Tax Credit gives tax credits to businesses that underwrite scholarships for students to attend private schools; it's being expanded. Why not fund the voucher idea entirely from these tax credits? That would allow businesses to help public-school students afford tuition at nonpublic schools - the goal of vouchers - without expecting the school districts and the students in them to shoulder the entire burden.