A great problem in U.S. education is that gifted students are rarely pushed to achieve their full potential. It is no secret that American students overall lag their international peers. Among the 34 countries in the Organization for Economic Cooperation and Development, whose students took the PISA exams in 2012, the U.S. ranked 17th in reading, 20th in science and 27th in math.

Less well known is how few young Americans—particularly the poor and minorities—reach the top ranks on such measures. The PISA test breaks students into six levels of math literacy, and only 9% of American 15-year-olds reached the top two tiers. Compare that with 16% in Canada, 17% in Germany and 40% in Singapore.

Among the handful of American high achievers, only one in eight comes from the bottom socioeconomic quartile. In Canada it’s one in four; Germany one in six; and Singapore one in three.

What has gone wrong? Thanks to No Child Left Behind and its antecedents, U.S. education policy for decades has focused on boosting weak students to minimum proficiency while neglecting the children who have already cleared that low bar. When parents of “gifted” youngsters complained, they were accused of elitism. It is rich that today’s policies purport to advance equality, yet harm the smartest kids from disadvantaged circumstances.

High achievers were taken more seriously during the Sputnik era. The National Association for Gifted Children was founded in 1954, the same year as the Supreme Court’s Brown v. Board of Education decision. As the country concerned itself with educational equity, John W. Gardner, the president of the Carnegie Corporation (and future U.S. secretary of health, education and welfare), posed a provocative question in a seminal 1961 book with the title, “Excellence: Can we be equal and excellent too?”

The year 1983 brought “A Nation at Risk,” the celebrated report of the National Commission on Excellence in Education, which declared that poor schools were contributing to national weakness: “Our once unchallenged pre-eminence in commerce, industry, science, and technological innovation is being overtaken by competitors throughout the world.” Five years later Congress passed the sole federal program to focus specifically on gifted students, which intermittently provides a modest $9 million a year for them.

Poor test scores show that gifted American children still aren’t reaching the heights they are capable of. How do other nations achieve better results? We set out to examine 11 of them—four in Asia, four in Europe, and three that speak English—for our forthcoming book, “Failing Our Brightest Kids: The Global Challenge of Educating High-Ability Students.”

Unsurprisingly we found that culture, values and attitudes matter a great deal. Parents in Korea, Japan and Taiwan push their kids to excel, and often pay for outside tutors and cram schools. So costly has this become, so taxing for parents whose children come home exhausted late at night, that families are apt to have only a single child—unwittingly contributing to their nations’ demographic crashes.

Finland is a different story. Equity and inclusion are the bywords, and teachers are supposed to “differentiate” instruction to meet the unique needs of every child. Elitism is taboo and competition frowned upon. Yet Helsinki boasts an underground of specialized elementary schools that parents jockey to get their children into. Most Finnish high schools practice selective admission, including more than 50 that, as a local education expert told us, “can just as well be called schools for the gifted and talented.”

In Germany and Switzerland, too, the high schools (“gymnasiums”) that prepare students for university are mostly selective. A handful also have intensive tracks with extra courses for uncommonly able youngsters.

Western Australia, like Singapore, screens all schoolchildren in third or fourth grade to see which of them show academic promise. Those who excel can choose to enter specialized classrooms or after-school enrichment programs. Both places also boast super-selective public high schools akin to Boston Latin School or the Bronx High School of Science.

Both Ontario and Taiwan treat gifted children as eligible for “special education,” much like disabled students, giving them access to additional resources. But these students are also squashed under cumbersome procedures: For instance, a committee must review their progress annually, and generally they may not transfer out of the school that the bureaucracy assigns them to.

What lessons can the U.S. take from this research on how to raise the academic ceiling, while also lifting the floor? States could screen all their students and offer top scorers extra challenges. They could encourage smart kids to accelerate through school or—more disruptive—allow every child to move through the curriculum at his own pace. Why must every 11-year-old be in fifth grade? Technology eases such individualization, but this change would also require agile teachers and major revisions to academic standards, curricula and tests that now assume every child should progress through one grade a year. Schools would have to ensure that extracurricular and social activities remain more or less based on age. But liberating fast learners to surge forward academically would do them—and society—a world of good.

If and when Congress finishes reauthorizing No Child Left Behind, it should encourage states to track and report not only progress by low achievers, but also academic gains by gifted students, as Ohio already does. Lawmakers should direct the Education Department to gather far better data on strong students than are available today.

For their part, states and school districts need to offer better options for high-ability pupils, such as schools that admit on the basis of academic potential, the way that Stuyvesant High School in New York City does. This model should be extended to middle and elementary school. Gifted poor children, in particular, need that kind of academic support from the start.

If we cannot bring ourselves to push smart kids as far as they can go, we will watch and eventually weep as other countries surpass us in producing tomorrow’s inventors, entrepreneurs, artists and scientists.

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