AUSTIN, Texas (AP) — Texas’ dramatically shifting demographics will be the focus Tuesday as attorneys representing about 600 school districts call their first witness in a trial in which the districts are suing the state over how it funds public education.

Demographer Steve Murdock, former director of the U.S. Census Bureau and ex-state demographer of Texas, is expected to testify about the explosion in the state’s Hispanic population, which has caused public school enrollment statewide to grow by an average of 80,000 students per year.

Six lawsuits have been filed on behalf of about two-thirds of Texas school districts, which educate about 75 percent of the state’s more than 5 million students. They have been rolled into a single case that opened Monday before state District Judge John Dietz in Austin.

Legal battles over school finance are nothing new in Texas: The latest case is the sixth of its kind since 1984.

At issue this time, though, is the Texas Legislature’s approval in 2011 of $5.4 billion in cuts to public education and grant programs. The districts are pressing for more funding, saying the cuts forced teacher layoffs and larger class sizes while running so deep that they violated the Texas Constitution’s promises to provide efficient, free public schools.

They say the system is now unfair because the cuts came at a time when school enrollments are skyrocketing and teachers are expected to prepare students for new standardized tests that are more difficult.

“The system of school finance, as we see it, is hopelessly broken,” said attorney Rick Gray, one of more than a dozen lawyers representing the different parties that have filed lawsuits. “It is not only inadequate, it is irrational, it’s unfair and, most importantly, it’s unconstitutional.”

Gray, who represents more than 400 districts in the suit, said during opening statements Monday that Murdock’s testimony will focus on how Texas is becoming majority Hispanic and how its average income is declining.

He said, “I think everyone can agree that education leads to higher earning” but also noted that poor schooling has the reverse effect by ensuring residents are ill-prepared for the workforce and are forced into low-paying jobs.

Gray said that if an education gap that has already begun forming is not corrected by 2050, it could cost the state of Texas $11 billion in tax revenue that it would have otherwise collected on higher wage-earners.

School districts say students from low-income families generally cost more to educate, with many requiring instruction to participate in costly remedial programs outside the classroom.

David Hinojosa, who represents another plaintiff, the Mexican American Legal Defense and Educational Fund, said that 60 percent of Texas students now receive free or reduced-price lunches at school.

The state Attorney General’s office argues that because Texas places great emphasis on local control of its school districts, shortcomings are the fault of individual districts — not the system as a whole.

Texas funded schools beyond the rate of inflation and enrollment growth between 2006 and 2010, and even with the 2011 cuts, districts still need “to show they are spending their money efficiently, Assistant Attorney General Shelly Dahlberg argued in court on Monday.

“Superintendents’ wish lists” include items such as iPads for students, and districts offer extracurricular programs including sports that aren’t required by the state, she said.

Standardized testing requirements that began last year are being phased in gradually, and passing them won’t be an absolute requirement to graduate until at least 2015, Dahlberg said. She also predicted that “almost every single” superintendent eventually called to testify in the case will concede that they expect their students’ test scores to continue improving over time — regardless of funding levels.

“I would suggest that we might have an impending crisis, but today it is not a crisis,” Dahlberg said. “And we do not believe the plaintiffs can meet their burden of proof to show that it is.”