Four years ago this week, President Bush signed into law the No Child Left Behind Act, designed to raise test scores and close the achievement gap between rich and poor and white and minority students. What has it achieved so far?
Claudio Sanchez, NPR education correspondent
David Dunn, chief of staff for the secretary of Education
Ross Wiener, policy director at the Education Trust
Joel Packer, National Education Association; manager for elementary and secondary education act policy