LET'S BE CLEAR. Philadelphia's public-school teachers are not responsible for the financial mess the district has found itself in.

Teachers are the heart and soul of the schools, who soldier on despite the battlefield conditions of recent years, while lacking adequate support staff and reaching into their own pockets to buy classroom supplies.

If you want to know who is to blame, look to Harrisburg. Look to a governor who cut nearly $1 billion from basic education aid in his first year in office and now has the gall to call himself the "education governor." Look to the Legislature, which has refused to face reality and admit that local schools - not just Philadelphia but the state's 499 other districts - need more state aid.

In an ideal world, the state would own up to its obligations, come up with a new and fair funding formula, and ease the pain of districts across the state by increasing the state's share from the historic low it is at now.

But, we do not live in an ideal world. We live in the real world, where solutions come hard and sacrifices are asked even of those not to blame for the schools' plight.

The taxpayers of Philadelphia have done their share. Smokers are paying $2 more a pack and the rest of us are paying an extra 1 percent in sales tax to help the schools.

The Nutter administration has done its share, increasing direct city aid to the district and championing its cause in Harrisburg, even though it meant support of higher local taxes.

The district's other unions have done their share, granting concessions - often under duress - in pay and benefits.

Now, Superintendent William Hite has turned to the Philadelphia Federation of Teachers to do its share.

The School Reform Commission yesterday voted to cancel the PFT contract with the district and impose a new provision dealing with health and welfare costs. Teachers, who currently do not pay for these benefits, will have to start chipping in. For the average teacher, who makes $72,000 a year, it will amount to paying $932 extra a year.

Those who make less will pay lower percentages.

The changes will bring in $44 million during the rest of this school year and up to $60 million in subsequent years. Hite is taking that money and putting it right back into the schools, restoring some of the vital programs and personnel cut in previous years.

Chair Bill Green argued that the SRC has the power to impose these terms under the provisions of the state takeover law. Obviously, the action will be challenged in the courts, and the PFT has already announced plans to do so.

Hite promised that no other provision of the PFT contract will be touched and will still be subject to continuing negotiations. We should all hold him to that promise.

But Hite is right about "shared sacrifices" - a phrase that has been his mantra for the last year. Just because we are not responsible doesn't allow us to shrug our shoulders and say, "It is not our fault." The lives and futures of children are at stake.

Sacrifices must be made, even by teachers. Is it fair? No. But it is the right thing to do.