I learned the phrase “24-seven” from a gifted African American student in Prince Georges County, Md. It was 10 years ago, and I was there to do a story on the restructuring of Benjamin Stoddert Middle School, an underperforming school in one of the nation’s largest majority-black counties.

I wonder where he is now, especially after reading a disturbing -- but not altogether surprising -- article in Education Week saying research shows that the greatest widening of the black-white achievement gap occurs not among the general population, but among higher-performing students as they move from elementary school into middle and high school.

In truth, I can’t tell you for sure that he was gifted, just that he was obviously very, very bright. Yet the sad truth was that students like him in Stoddert’s gifted and talented classes would be merely performing on grade level if they moved across the Potomac River to the more affluent areas of Arlington or Fairfax County. That’s what happens, researchers note in the article, if the general population is doing poorly: Teachers tend to teach to the middle, and the middle at Stoddert, located near the distressed neighborhoods that border Washington, D.C., was lower.

After several years of being taught at a level lower than students at more affluent schools, it’s no wonder that the achievement gap tends to widen most noticeably at the top.

There are other possible reasons for this trend. Just as there can be disadvantages in attending a majority black school, some African Americans may feel out of place in an overwhelmingly white one -- and determined not to “act white” and do their best. Out-of-school disparities among families can exacerbate the achievement gap as well: think of the academic advantages provided by computer camps, piano lessons, and private tutoring.

Finally, add the influence of NCLB and its single-minded focus on raising the achievement of students who test below state standards. It’s a worthy goal, of course, but there are fewer of these students in the more affluent schools, and that encourages the teachers in these schools to adopt a more enriching curriculum across the board.

The high-end achievement gap is a serious challenge for board members, teachers, and administrators. But it’s not insurmountable. And educators, who tend to be optimists by nature, know that. The more we learn about the reasons for the achievement gap, the more effectively we can begin to reduce it and move toward a public education system that offers all students the chance to reach their potential. Education is not the only tool in the struggle for equal opportunity and social justice, but it is indispensible.

Lawrence Hardy, Senior Editor