Gov. Corbett on Tuesday proposed cutting more than $1 billion in funding for public schools, a move that could trigger tax increases, program cuts, and teacher layoffs throughout the state.

The Philadelphia School District's projected shortfall next school year alone could balloon to more than $600 million as a result of the cuts, a knowledgeable source said.

Suburban school districts, while not as hard-hit, face the loss of tens of millions in funding as well.

"There's only one place for it to come from - that's by cutting programs and people," Upper Darby Superintendent Louis DeVlieger said. "My heart breaks. We're going right to the bone - there's no flesh to cut here."

Confronting a more-than-$4-billion deficit in the overall state budget, Corbett said Pennsylvania's education funding had to be slashed to make ends meet. He proposes a more than 11 percent cut in his public school budget of $8.9 billion.

In Philadelphia, it means more fiscal misery for a district that had already been bracing for a funding gap of more than $400 million.

Michael J. Masch, the district's chief financial officer, estimated Tuesday night that the district would lose about $100 million in state funding under Corbett's plan.

When the loss of federal stimulus funds to the state budget was factored in, the School District would see a drop of $290 million, Masch said.

He declined to comment on the report that the district's shortfall would grow to $600 million.

If Corbett's cuts are enacted, predicted Jerry Jordan, president of the Philadelphia Federation of Teachers, increased class sizes, layoffs, and the elimination of programs such as advanced placement, music, and art in the city schools, which enroll 154,482 students.

"The state budget proposed [Tuesday] will reverse eight years of academic progress by slashing funding to vital programs created to put our students on equal footing with well-funded, high-achieving school districts," Jordan said.

About $110 million of the proposed cuts in Philadelphia would come from Corbett's plan to stop reimbursing districts for a portion of their charter-school costs.

The city's 74 charter schools enroll more than 43,000 students.

"I am concerned about the impact that the elimination of the charter-school reimbursement will have on the resources available for all young Philadelphians in our public school system," Mayor Nutter said.

He also lamented the loss of the district's accountability block grant - $55 million - which it has used to fund full-day kindergarten. Masch said Philadelphia also would lose an additional $55 million that the district has used to help cover summer school costs and provide after-school tutoring for students who are struggling.

In area suburban districts, administrators already grappling with multimillion-dollar budget deficits fear they may face much larger gaps.

Many had anticipated cuts in the Basic Education Fund allotment, the state's largest payment to school districts.

So it was no surprise that in Corbett's proposal, basic education funding would be cut about $550 million - a 9.5 percent reduction that would put it back to about the 2008-09 funding level. Philadelphia's suburban districts would see their allocations reduced about $48 million.

Corbett's proposed cuts to the education budget went far beyond that, however.

The elimination of three programs - tutoring, charter-school reimbursements, and the block-grant program, which schools use for everything from kindergarten programs to reducing class size - would take more than $500 million away from local districts.

About the only substantial increase in the proposed budget is for school employees' pensions. That went up more than $327 million.

The governor also called for establishing an independent authorizing agency to consider applications for new charter schools and renewals for existing charters.

In the suburbs, anxiety about the Corbett proposal was palpable.

Delaware County's Upper Darby School District, for example, depends on state funding for about 35 percent of its revenue.

The district had already been grappling with a $9 million difference between expenses and income for next year.

Now, it is facing $3 million more in state cuts than it expected, said DeVlieger.

"I feel like the trust of the citizens will be broken," he said. "We're either going to drive them out of town with the tax increases, which we're not going to do, or to drive them out of town by not offering the programs they've been accustomed to. It's a sad day."

Administrators in more-prosperous districts were also left reeling.

In Chester County's Downingtown Area School District, which gets about 20 percent of its funding from the state, the Corbett cuts would amount to more than $3 million.

The district had planned on losing about $1 million, said Superintendent Lawrence Mussoline.

"We already needed to cut $8 million just to get down more," he said. "The loss will cut more away from our educational core. This is very painful. . . . I hate to see state government using public education as a whipping post. We can tighten our belt, but I'm disappointed."