Have efforts to improve schools neglected high achievers? A growing chorus of critics is voicing concern for the achievement gap, but not the gap between well-to-do and poor students, or white and non-white students. The gap that most worries them is the one between U.S. students and students in other industrialized nations. Among the 34 nations in the Organization for Economic Cooperation and Development (OECD), for example, the United States ranks 14th in reading, 17th in science, and 25th in mathematics. And the U.S. high school graduation rate of 76% falls below the OECD average of 80%. The author looks at how one of the nation's best schools helps its best students continue their advancement. (Contains 1 table.)