This report contains two separate studies examining the status of high-achieving students in the No Child Left Behind (NCLB) era. Part I, An Analysis of NAEP Data, authored by Brookings Institution scholar Tom Loveless, examines achievement trends for high-achieving students (defined, like low-achieving students, by their performance on the National Assessment of Educational Progress, or NAEP) since the early 1990s and, in more detail, since 2000. Part II, Results from a National Teacher Survey, authored by Steve Farkas and Ann Duffett of Farkas Duffett Research Group, reports on teachers' own views of how schools are serving high-achieving pupils in the NCLB era. A foreword by Chester E. Finn, Jr. and Michael J. Petrilli, states that the major finding of this dual study is that, in one respect at least, NCLB is working precisely as designed. A good thing, surely, but not entirely so. What we see in this study is one of its unintended consequences--and one that's worrisome for America's future competitiveness. A positive trend is that our low-performing students are starting to make respectable gains, but if gains by low achievers are our only measure of success, America faces big challenges in the years ahead. Part I appendixes present: P-Values for Gains at the 90th and 10th Percentiles in the Era of NCLB; P-Values for Gains at the 90th and 10th Percentiles Pre-NCLB; Descriptive Statistics and Standard Errors; and Sources for Independent Variables in Question 4. Part II appendixes present: Methodology; and National Survey of Public School Teachers Grades 3-12. (Contains 15 tables, 36 figures, and 34 notes.)