When the No Child Left Behind Act of 2001 (NCLB) was drafted and signed into law, little attention was paid to the unique challenges that exist in the nation's high schools and what is best known about how to improve them. As a result, the law emerged with provisions that often neglect, or that are even at odds with, the needs of America's millions of high school students, particularly the six million students who are most at risk of dropping out of school each year. The brief describes these design and implementation flaws and how they undermine the educational and equity promises of NCLB at the high school level. "In Need of Improvement: NCLB and High Schools" calls on Congress to take the opportunity during the reauthorization of the law to build on the ideals of "no child left behind" and pass legislation that will lead the nation toward "every child a graduate." (Contains 13 endnotes.)