Much has been written about achievement gaps in the United States, with even more energy and dollars devoted to reducing them, for decades now.

Not only has seeking to help low-income and minority children do much better academically been an essential quest -- one that must continue -- but it's also fair to say it has been at the very core of our attempts to significantly improve American elementary and secondary education.

Yet it's also fair to say that another large achievement gap has been mostly ignored over this same long period: The dangerous distance between America's strongest students and their counterparts around the world -- with top pupils elsewhere consistently coming out ahead.

Just one example: Six percent of U.S. students perform at what's called "advanced proficiency" in math. This is a smaller proportion than in 30 other nations.

As for Minnesota students, it's satisfyingly true that in general kids here do better than boys and girls in most other states. But if we think of each of the 50 states as an independent country, not a single state -- very much including Minnesota -- would rank among the top dozen nations, give or take.

Stanford economist Eric Hanushek is a leader in explaining why this is important.

Focusing on math and science, he notes "considerable evidence" that cognitive skills in those areas are "directly related" to individual earnings and productivity. But, he crucially adds, if the relationship between cognitive skills and individual outcomes is strong, the relationship between labor force quality and economic growth for a nation overall is even stronger.

As a state and nation, we will increasingly depend, economically, on miraculous technological breakthroughs wrought by superbly educated men and women. Yet for whatever reasons and to our collective detriment, in our efforts to better serve struggling students, we have insufficiently helped our most talented young people be all that they can be, too.

For a telling reflection of this, try Googling the term "STEM," standing for "Science, Technology, Engineering and Math" education. The weight of reports and news stories is overwhelmingly focused on how our weakest students are faring in these key areas -- rather than on how our best students are doing. The disparity isn't even close.

If our interest is in more fully serving all students, the iconic "Nation at Risk" report, released in 1983, correctly framed the destination and tension this way: "The twin goals of equity and high-quality schooling have profound and practical meaning for our economy and society, and we cannot permit one to yield to the other either in principle or practice."

Sticking with STEM, three of the best-known selective STEM high schools in the United States are in New York City: Stuyvesant, Brooklyn Tech, and the Bronx High School of Science, with the trio having produced a dozen Nobel laureates along the way.

But as successful as they have been in one of our most politically egalitarian cities, there are relatively few three- and four-year academically selective high schools across the country -- only about 165 by one accounting, with populist Minnesota home to none.

Great numbers of people, of course, contend that this is exactly as it should be -- that the very notion of admission to a public high school based on what might be innate skills is offensive to the point of being undemocratic. It's a powerful argument to which an even more potent rejoinder is required.

In venturing one, I'm proud to call as my lead witness one of Minnesota's great champions of Everyman, Everywoman and Every Student: the late Rudy Perpich, a DFLer who, in two nonconsecutive stretches in the 1970s and '80s, served as governor for a total of 10 years, longer than anyone else in state history.

Largely forgotten is how Perpich, in 1987, proposed a state science and math boarding school modeled after one in North Carolina. Two years later, in 1989, he again proposed a math and science academy, this time modeled after one in Illinois, calling for a public-private partnership to make it happen.

More recently, in 2006, Rep. Melissa Hortman, a DFLer from Brooklyn Park, proposed a math and science high school for the state, with Republican legislators also expressing support, before the idea faded once more.

For reasons of both private and public benefit -- the kind of we're-all-in-this-together argument Perpich was known to make -- let me suggest that this is a project warranting revival and realization. Let me also raise several early questions and answers.

Would Minnesota students attending a selective STEM high school, in fact, do better than they otherwise might?While there has been surprisingly little research in this area, it's certainly fair to assume that for many extra-talented students, consistently collaborating with and competing against peers who are at least as talented as they are is exactly what they need in order to be all they can be. A recent study by three scholars, including education psychologist Rena Subotnik, found that students entering a selective STEM school with a "deep interest" in such subjects are significantly more likely to later graduate college with a degree in one of them than are similarly smart and inclined students attending regular comprehensive high schools.

I would add it's also fair to assume that for many extra-studious students, attending a school in which terms such as "nerd" are expressions of camaraderie rather than bullying slurs is likewise a benefit.

How might a selective STEM high school resist charges of elitism? How might it resist even more damaging charges of insufficient student diversity, if that proved the case?As for the first criticism, the only answer is that the school proposed here is absolutely meant to be an elite institution. The very idea is to help a significant number of Minnesota's strongest students learn and grow to be even stronger, not just for their own sake, but for our state's and nation's well-being, too.

Questions more specifically regarding racial and ethnic diversity are more difficult, especially given how achievement gaps in Minnesota are bigger than just about other place in the country. Suffice it to say that implicit in this kind of institution must be a commitment to statewide outreach. This might mean, for example, running year-round, geographically dispersed programs aimed at helping low-income and minority middle school students excel. Girls outnumbered boys, by the way, in the selective schools studied by Subotnik.

What might running such a school cost?This is impossible to answer without knowing how many students would attend, whether the school would be residential or not, and so on. But keep in mind that educational dollars in Minnesota mainly follow students, likely nullifying the need for new, budget-busting public outlays; students would be funded at whatever public school they attended. And just as Rudy Perpich saw a public-private partnership as pivotal, a commitment to collaboration remains indispensable so as to keep public expenses as close to revenue-neutral as possible.

Who should lead and teach at such a school?If there is one bottom-line requirement anywhere in this venture, it's here. Teachers must be true experts in the subjects they teach, and a principal must have the authority to both choose and sometimes let them go, free of the excessive constraints regarding licensing, seniority, terminations and such routinely gumming up most public schools. They'd also need to be free from rules that prevent top-flight mathematicians, scientists and engineers from teaching.

What kind of curriculum?In addition to course offerings being deep in STEM subjects, they must be equally strong across the board, as the essence of an exceptional high school education is that it is an exceptionally well-rounded one. It goes without saying, moreover, that students and teachers would take advantage of all manner of digital learning opportunities.

What kind of admission policies?Selective high schools are often called "exam schools" for a reason. While no claims are made that any multiple-choice test could ever fully capture a person's potential, it's inescapably true that in order to succeed in a school of this kind, students must be very good when it comes to the types of skills and knowledge measured by standardized tests.

Yet having said that, there's more to evaluating young people's wherewithal, starting with heart and determination, than running penciled dots through a scanner.

-----------------------------

Mitch Pearlstein is founder and president of the Center of the American Experiment in Minneapolis. His most recent book is "From Family Collapse to America's Decline: The Educational, Economic, and Social Costs of Family Fragmentation."