by Lyndsey Layton

The National Center for Education Statistics released a new analysis Thursday that looks at how public school students in the five largest states performed in math and reading tests between 1990 and 2011. The report also included a few years of science test results.

The data were collected from the National Assessment of Educational Progress (NAEP) exams, which are regularly given to fourth- and eighth-graders across the country and are known as “the nation’s report card.”

The states that are the focus of the new study — California, Texas, Florida, Illinois and New York — educate about 40 percent of the country’s public school children. They are home to 3.4 million of the country’s 9 million families who are living below the poverty line.

The states posted mixed test results, depending on the grade, subject and subgroup of students tested. Jack Buckley, the commissioner of the National Center for Education, said it was difficult to detect significant trend lines.

“There isn’t any one state that jumps out for no good news or no bad news,” Buckley said. “These are complex states, and they have different challenges in terms of what kinds of kids they have to educate and their resources when they show up at the school door.”

Still, some interesting data points emerged. Most students in California, for example, scored below the national average in reading in grades 4 and 8 in 2011, while all groups of fourth-graders in Florida scored above the national average.

“There is something real going on there,” Buckley said, referring to Florida in a conference call with reporters Wednesday.

Shifting demographics in the five states reflect changes taking place across the nation. There was a decline in the percentage of white students, from 73 percent in 1990 to 54 percent. During the same period, the percentage of Hispanic students in the five states rose from 7 percent to 23 percent, Buckley said.