Note: To use the interactive map visit newsworks.org
School district enrollment levels have dramatically shifted in Pennsylvania over the last 25 years.
Many rural districts in the western part of the state have seen steep declines, while many urban, suburban, and eastern districts have grown. In all, more than a third of the state's 500 districts have either grown or shrunk by more than 25 percent since 1991.
That was the year the state implemented a "hold harmless" policy, which dictated that enrollment fluctuations would not affect state funding allocations. So, for decades, all districts received the same inflationary boost to funding no matter whether, for instance, they gained or lost hundreds of students from year to year.
Over time, this has greatly affected the equity of the state's school funding. And for those on the losing end, this contributed to decades of strife.
As detailed in a previous Keystone Crossroads analysis, "hold harmless" has been a major boon for districts where student population has declined and has been a major challenge for many of the districts where enrollment has spiked.
Eighty-six school districts have seen their student populations grow by 25 percent since 1991.
Many of these are wealthier, suburban and exurban districts, but some are among the poorest in the state.
And it's to these districts that state policy has been most cruel.
Reading, Allentown and Lebanon have seen tremendous population growth while being tasked with serving some of the poorest, most needy students in Pennsylvania.
But the state has not systematically acknowledged these burdens or the enrollment spikes.
"It's created a confluence of issues with educating our students," said Reading Superintendent Khalid Mumin. "It's not adequate."
This year, though, lawmakers implemented a student-weighted funding formula in order to add more realistic factors to its funding distributions.
This begins to rectify the logic of the past.
But even with the formula in place, districts historically shorted will continue to struggle. Lawmakers only plan to use the formula — which counts factors such as actual enrollment, poverty and language fluency — to disburse only new increases in state aid.
Currently, that means 94 percent of the pot of state basic education funding ($5.5 billion) is still distributed without taking enrollment or other student-based factors into account.
Of the 168 districts where enrollment has risen by 5 percent or more since the state enacted "hold harmless," 13 serve some of the poorest students in the state.
They are Allentown, Carbondale, Erie, Hazleton, Lancaster, Lebanon, Minersville Area, Panther Valley, Philadelphia, Reading, Scranton, Shenandoah Valley, and York.
Of these, only York cracks the top 25 in per-pupil state basic education funding.
Philadelphia specifically was hurt in the first few years of hold harmless, as it added tens of thousands of new students without any systematic acknowledgement from the state.