By Natasha Brown

HARRISBURG, Pa. (CBS) — A trial is underway in Harrisburg with potentially huge ramifications for education across the Keystone State. It has to do with tax dollars and how schools are funded.

A spirited rally was held in Harrisburg as the trial in the Pennsylvania school funding lawsuit opened Friday in Commonwealth Court.

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The historic lawsuit filed seven years ago challenges the constitutionality of the state’s school funding system, with plaintiffs arguing that it creates wide, inequitable resource gaps between school districts.

The case is brought by six Pennsylvania school districts, including the William Penn School District in Delaware County, four parents — including a Philadelphia parent — along with the state NAACP and the Pennsylvania Association of Rural and Small Schools.

At the heart of the case is the huge financial divide in resources between richer and poorer school districts with funding systems that rely heavily on local taxes. Plaintiffs say the system disproportionately hurts Black and brown children in lower-income communities.

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For example, the wealthier Lower Merion School District reportedly has $31,000 to spend per student because it can receive more from higher property taxes. Poorer districts, like William Penn, have only about $18,000 per student at their disposal.

“Probably the most important school funding and constitutional court case in a generation,” Philadelphia City Councilmember Helen Gym said.

Gym, a long-time education advocate, rallied in Harrisburg just outside of the courthouse. She explains how this landmark case could affect students in the Philadelphia region.

“I would say that the state legislature over decades has robbed the schoolchildren, families and our city of billions of dollars in funding. There’s no question that even if according to the fair funding formula if it were duly allocated, the city of Philadelphia, the school system would receive hundreds of millions of dollars more,” Gym said.

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The case is expected to take several weeks with many witnesses from school districts taking the stand. If the court rules in favor of the plaintiffs revamping the way Pennsylvania schools are funded, without relying heavily on property taxes, would be an issue that the state legislature would have to take up and try to resolve.