TRENTON, N.J. – A new study by a Stanford University research center shows students in New Jersey charter schools have demonstrated greater learning gains overall than their traditional school counterparts.

The study, released by the Center for Research on Education Outcomes (CREDO) earlier this month, contained mostly good news for the state’s charter schools, reports Philly.com.

“These schools are excelling with a high proportion of minority students in poverty,” read the report.  “These schools’ practices may be instructive for other public schools that also serve this student group.”

MORE NEWS: Know These Before Moving From Cyprus To The UK

The study showed charter school students in grades 3-8 gained an additional three months of learning per year in math and reading compared with their peers in regular public schools, according to the news site.

Nearly one-third of charters showed significantly higher achievement levels in reading than the other public schools in their districts, with only 11 percent doing worse. The gains were even greater in math, where 40 percent of charters outperformed their traditional counterparts.

New Jersey has more than 80 charter schools, with more than 30,000 students.

The study, which is the first to take an in-depth look at the state’s charter school system, evaluated school data from 2006-07 through the 2010-11 school years.

New Jersey Education Commissioner Chris Cerf said the results are the fruition of hard work.

CREDO’s report “reflects the work we have undertaken…to increase our accountability standards, strengthen the rigor of our authorizing process, and, when necessary, close schools that are underperforming,” said Cerf.

MORE NEWS: How to prepare for face-to-face classes

The report also struck a chord with charter school organizations. Gloria Bonilla-Santiago, chair of Camden’s LEAP Academy University Charter School, said the study further validates the importance of charter schools.

“It highlights the debate about what charter schools bring to student performance; we are growing and doing better,” said Bonilla-Santiago. “What makes charters unique is the quality of teaching and the care we provide to our students.”

Steve Baker, a spokesman for the New Jersey Education Association, said the numbers do not point to clear policy conclusions, due to differences in student demographics.

“It’s good news any time students are doing well,” said Baker. “[But] you have to be very careful about thinking about this as an apples-to-apples comparison.”

CREDO director Margaret Raymond disputed Baker’s comment, saying the students selected for the study have many similar demographic characteristics.

New Jersey charters performed better overall than those in a 2009 CREDO study of charters in 15 states and the District of Columbia, and better than Pennsylvania charters in a 2011 study, according to the news site.