According to education officials, there are two kinds of expansion - good growth that helps boost a school district's tax base, and bad growth that merely escalates expenses.
Good growth is the kind that brings large commercial or industrial projects into a school district. It could also be the kind of growth that brings many large residential developments to a school district with room to expand.
That kind of growth, school district officials said, means more tax dollars for public schools and little need for tax increases.
It is the kind of growth that is occurring in outlying suburbs such as Downingtown in Chester County, where school officials have been able to plan expansion projects for next year without an increase in school taxes.
Bad growth is the kind that some suburban school districts near the borders of Philadelphia are facing.
It is the kind of growth that brings families with young children into suburbs where the tax base is stagnant or rapidly declining.
For those suburban school districts, such as the William Penn School District in Delaware County, growth in enrollment just means a jump in the cost of schooling.
"We've been experiencing growth in enrollment for the past three years," said John Dirnbauer, superintendent of the William Penn School District.
"Our elementary school buildings are overcrowded. Probably in 1987-88, we'll have to get temporary classroom units," Dirnbauer said, explaining that the district expects to have 2,774 elementary school students next fall, about 200 more than just three years ago.
But, he added, as the district's costs continue to increase, its tax base continues to decrease, forcing the school district to keep raising taxes to stay financially afloat.
"There has been virtually no new construction going on here," Dirnbauer said, explaining that the total value of taxable property in his school district has dropped 19 percent since 1981, while taxes have gone up 25 percent.
Earlier this year, Dirnbauer gave the William Penn school board a proposed 1987-88 budget calling for a 65-mill tax increase that would have raised the
average tax bill by $195.
Even with the tax increase, Dirnbauer predicted that the district would have to cut music, art and sports programs to remain financially stable. It was a proposal that angered school board members and prompted about 500 high school students to stage a walkout.
Since then, the school board has managed to save the art, music and sports programs and reduce the tax increase to 40.7 mills to fund the $24.4 million budget. To reduce the increase, the school board agreed to cut its budget reserve to zero, cut substitute teachers' salaries and eliminate professional travel for all employees.
Still, the tax increase has raised the William Penn School District's tax rate to 334.7 mills, one of the highest in the Philadelphia suburban area, Dirnbauer said. One mill represents $1 tax for each $1,000 of assessed property value.
"Growth can be really misleading," Dirnbauer said, "especially because we are seeing a growth in population without a truly corresponding growth in available resources to fund the growth in enrollment."
Other school districts facing rapid growth in enrollment and slow growth or a decline in the tax base include the Upper Darby and Chester-Upland School Districts in Delaware County, the Cheltenham School District in Montgomery County and several smaller ones in New Jersey.
"Growth is a double-edged sword," said William Hartenstein, business manager for the Cheltenham School District. "As the student population grows, we have to take care of them by adding books and hiring teachers. We have a lot of new kids, but no broadening tax base."
NOT IN PROJECTS' PATH
The Coatesville Area School District is in a similar situation.
Although it is in fast-growing Chester County, it is not in the direct path of the new industrial projects that have been attracted to the area.
In fact, the school district's largest commercial taxpayer, the Lukens steel mill, won a reassessment appeal in 1983 allowing the company to cut its tax bill by about 55 percent, or about $4 million.
That has deprived the school district of nearly $1 million in annual revenue at a time when student enrollment is increasing and costs are escalating, school district officials said.
"The kind of growth that people seek, of course, is the industrial type," said Roy Moore, business manager for the Coatesville School District.
"You can have somebody build a home or move into a mobile home and have five or six children, and no way would you have a growth that would offset the expense. . . . You have to lay out the money for textbooks and supplies," he said.
"These malls and shopping centers that come in - now, that would increase the tax base. We aren't experiencing the same kind of growth that Downingtown and West Chester are. Other school districts are growing so rapidly that they can absorb the cost because of an expanding tax base, but our tax base isn't growing nearly as rapidly."
According to statistics compiled by the state, the assessed value of the Downingtown School District, which borders Coatesville's district, increased by $33.7 million since 1980. The Coatesville School District's taxable value, however, has increased by only $2.7 million since 1980.
Many school district officials and economists believe part of the problem lies in the way the state determines the taxable value of real estate.
"Typically, in the five counties around Philadelphia, the (taxable) assessment value is around 20 percent of the market value," said Thomas R. Luce, associate director of the Wharton-Philadelphia Economic Monitoring Project at the University of Pennsylvania Wharton School of Business.
That means that if a homeowner has a house with a market value of $100,000, the taxable value of his property would be $20,000.
"As the market value goes up, assessments aren't going up at the same time," Luce said. "And that tends to mean that over the course of the years as market values increase, school districts have to raise taxes in order to capture that increase."
Luce said that although some areas of the state had recently undergone property reassessments, lawmakers had shunned moving toward a statewide reappraisal of property.
"Simply because it is costly to reassess," he said, explaining that state or local governments would have to pay to have appraisers survey and re- evaluate land values.
"It costs less to just raise the tax rate," Luce said. "All you have to do is pass a resolution."
Because of the low assessments of real estate in the Philadelphia area, many school district officials say that the real estate tax that funds the major portion of school district budgets is inflexible and does not bring in enough money.
Some educators around the state have joined to lobby for a change in the taxing system during the forthcoming special legislative session on tax reform called by Gov. Casey.
"There's a lot of concern about the whole mix of taxes," said James Shields, who is in charge of governmental relations for the Delaware County Intermediate Unit. "Some school districts would like to have the flexibility to have a tax on income. By having an income tax, districts would have a better chance of tying into the growth of the area.
"The real estate tax is not money in your pocket, but it's the only thing we have right now, and because it is, millage rates are going to continue to go up."