After more than eight weeks of testimony, the plaintiffs challenging Pennsylvania’s school funding system expect to rest their case Wednesday.

The landmark trial — centered on allegations that Pennsylvania’s method of funding public education is so inadequate and inequitable that it violates its constitution — has featured accounts of underfunding from school districts across the state, including six who brought the lawsuit. Experts have testified how school funding affects academic performance, graduation rates, and life prospects.

Starting Monday, Republican legislative leaders, who are defendants in the case, will have a chance to call their own witnesses. (Democratic Gov. Tom Wolf, who is also a defendant but hasn’t opposed the claims, may call one witness, his lawyer said.)

Here are some of the highlights from expert witnesses in the final days of testimony:

Future earnings increase when pupil spending goes up

When it comes to how well students do in school and later in life, the amount of money their schools spend matters — and courts can play a big role in directing funding changes that reduce achievement gaps, said Rucker Johnson, a public policy professor and labor economist at the University of California-Berkeley.

Johnson testified about research he conducted using a nationally representative sample of 15,000 people, comparing outcomes from those who attended schools in states where courts ordered education funding reforms in response to large spending gaps between wealthy and poor districts — 28 states between 1971 and 2010 — with those who didn’t.

The average school-funding reform led to a 10% to 15% increase in per-pupil spending, Johnson said, and it had an impact: For low-income children, a 10% funding increase sustained for 12 years of schooling meant a 10% increase in future earnings, and a 6% decrease in the likelihood of being poor as an adult.

In states with funding reforms, the achievement gap between children from low- and high-income families decreased over time, while the opposite occurred in states without them, Johnson said.

“The overwhelming, consistent pattern” in recent research finds achievement gaps are reduced if states spend adequately on public education, and distribute more money to school districts with students with higher needs, Johnson said.

Benefits of better funding double if students have quality pre-K

How money is spent also matters. Increased funding for early childhood education coupled with increases for K-12 schools provides “the biggest bang for the buck,” Johnson said.

While high-quality pre-kindergarten boosts achievement, there is “evidence of fadeout” of those benefits if students then attend poorly funded K-12 schools, he said. On the other hand, the impact of K-12 funding increases doubles if students first have access to quality pre-kindergarten, Johnson said.

He pointed to New Jersey, where the Abbott v. Burke cases reshaped school funding, steering more money to poorer districts: In 1990, for every dollar spent in high-income New Jersey school districts, low-income districts spent 81 cents. By 2011, low-income districts were spending $1.08 for every dollar spent by their higher-income counterparts.

The changes also included investment in pre-kindergarten, which made the K-12 spending increases “more efficacious in leading to higher student achievement,” Johnson said.

In Pennsylvania — which relies heavily on local property taxes to fund public education — low-income districts spent 79 cents per dollar spent in high-income districts in 1990, compared with 91 cents in 2011. While the state in 2016 adopted a funding formula that distributes more money to needier districts, it applies to less than 15% of the main state subsidy.

The funding gap facing students in poorer districts is hindering their chances of success, Johnson said.

“I’m not saying there aren’t some students overcoming the odds,” he said. “I’m saying the support from the state’s funding system is systemically making the odds steeper, more difficult, and unfair on equity grounds.”

Lawyers for legislative leaders questioned the impact of additional funding. “Has school reform broken the cycle of poverty in Camden, N.J.?” said Patrick Northen, a lawyer for House Speaker Bryan Cutler.

“We’re not focusing our results on one district,” Johnson said, but looking at large numbers of students.

Erase college education gap, and local taxes would see $1.2 billion gain

If students graduate from college, not only do they earn more on average than high school graduates and have better life outcomes, but their communities and the state as a whole also benefit, another economist testified.

Clive Belfield, an economics professor at Queen’s College, City University of New York, modeled “expected life course outcomes” for Pennsylvania students with different levels of educational attainment, based on research that he said showed “robust” relationships between years of education and lifetime earnings, tax contributions, health outcomes, and participation in criminal activity.

He then calculated the expected benefits — from those experienced by individual people, to broader fiscal and social benefits. For instance: The social gains to a community from a person attending some college compared with graduating from high school are worth $150,000, Belfield said — accounting for the cost of sending the person to college, but then higher earnings, lower expected health-care costs and less crime, among other factors. If someone receives a bachelor’s degree, the social gain compared with attending some college would be $623,000.

Of students Pennsylvania considers economically disadvantaged, 44% attend some college, compared with 69% of non-economically disadvantaged students, Belfield said. Only 22% of economically disadvantaged students receive a degree, compared with 47%.

If all students attended college at the same level as those without economic disadvantage, Belfield said, Pennsylvania each year would gain about $4.5 billion in federal taxes — money spent “almost one-to-one” in the state — and $1.2 billion in state and local taxes.

It’s not the algebra but the discipline of learning

Nancy Hacker spent 45 years in education, including eight as superintendent of the Springfield, Montgomery County, school system. But she also spent time as an administrator and teacher in less wealthy districts, including Penn-Delco and Interboro.

The difference between Springfield — where if class sizes got too large, she had the resources to simply hire another teacher — and the poorer districts was vast, she said. In Interboro, for instance, “there were significant gaps in terms of what we were able to provide to students,” Hacker said.

The percentage of students from low-income families more than doubled during Hacker’s years in Springfield, growing to 20% by the time she retired in 2020, and the school system had to make adjustments to accommodate them, hiring school psychologists, counselors, additional teachers, and support staff. Was Springfield able to successfully educate all students, including children from economically disadvantaged families, English language learners, and others?

”We certainly had the resources to work very hard at doing that, yes,” said Hacker.

Asked whether she thought higher-level academic courses were important for all students, Hacker said she did. Though she doesn’t employ algebraic thinking often in her everyday life, learning it has “served her well,” said Hacker, adding that while not all children should or will go to college, they all deserve the chance to be prepared for it.

”It’s the science of learning, it’s the discipline of learning … that helps children later on in life after they graduate to make better choices for themselves,” Hacker said. “We want to ensure they have as wide array of choices as possible and they learn the thinking and the discipline and persistence involved in those content areas.”