in 2011, gifted students from 12 historically black colleges and universities prepare to show their knowledge of African American history at the Black College Quiz Game Show, at Howard University in Washington, D.C. (Jahi Chikwendiu/The Washington Post)

Broward County, Fla., launched a remarkable experiment a decade ago. Instead of depending on teachers and parents to nominate children for IQ testing leading to gifted designations, the district gave a preliminary giftedness test to all second-graders.

Most of us assume the way we select gifted children catches nearly all students ready for advanced instruction. But Broward County schools proved otherwise, according to economists David Card of the University of California at Berkeley and Laura Giuliano of the University of Miami.

All second-graders took a short test on shapes and designs. Those who scored well were given a three-hour IQ test. That produced a big jump in the number of third-graders who met the IQ standards for the district’s gifted program. The additional students were disproportionately poor, black or Hispanic and more likely to have parents who spoke a language other than English.

The increase was mind-

“With no change in the minimum standards for gifted status,” the authors said in their paper for the National Bureau of Economic Research, “the screening program led to a 180 percent increase in the gifted rate among all disadvantaged students, with a 130 percent increase for Hispanic students and an 80 percent increase for black students.”

When the program began in 2005, non-disadvantaged students needed a minimum 130 points on the IQ test to receive gifted services. Students who were poor or still learning English had a lower 116-point threshold. Even with that adjustment, only 28 percent of gifted students in third grade were Hispanic or black, in a district where those ethnicities make up 60 percent of the total enrollment. Thirteen elementary schools in poor neighborhoods had no third-grade gifted students at all.

Under the new system, parents and teachers could still nominate students they thought should be IQ tested. Parents could have their students tested privately and submit those scores. “There is a thriving private market for IQ testing in the district,” the researchers said, “with many psychologists offering first-time IQ tests and re-testing for children who failed to meet the state mandated standards on an earlier test.”

In Broward County, some experts expressed concern that even if poor and minority students tested well enough to take gifted classes, they would not have the middle-class study habits and parental support to succeed. Card and Giuliano cited suggestions that “the newly identified students may also disrupt the quality of gifted services for other students, undermining the value of the program.”

But when the researchers looked at the distribution of test-score gains for third- and fourth-graders, there was no sign of the disadvantaged students having any disruptive effect on the scores of gifted students selected from the usual families. The data suggested that “the newly identified students benefitted even more from participating in gifted education” than the students who had been identified under the traditional system, the researchers said.

Why did the teachers and parents who nominated gifted candidates miss so many disadvantaged children? Poor and immigrant children tend to have lower test scores and grades on average, the researchers noted, which might have led people to assume that few of them had the intellectual potential of more-privileged kids.

Today, Broward has more students designated gifted than ever before, district spokeswoman Cathleen Brennan said. Most Washington-area school districts have also moved to testing all students, but nationally, little has changed.

National Association for Gifted Children board chair George ­Betts said, “Few states require universal screening for giftedness.” He also said, “Gifted education programming is not mandated across the country, [and] universal screening is expensive.” The standard educator and parent referrals, he said, are not enough to identify all gifted students.

That seems obvious. It is time for school districts to explain what their designated gifted children are getting that is important, and why they don’t offer it to minority and poor kids who are just as smart.