SUBPAR SUBURBAN: Arthur Levine presents a colorful economic analysis of a lesser-known achievement gap in this WSJ op-ed. The former president of Columbia University's Teachers College warns that there's a vexing gap between students in America's top suburban K-12 schools and their international counterparts. Only students in a few US suburbs (notably Evanston, Ill., and Scarsdale, N.Y.) stack up well against schools in places like Finland and Singapore. "Stanford economist Eric Hanushek has estimated that America would add $1 trillion annually to its economy if it performed at Canada's level in math," he notes. Levine doesn't ignore the problems at home. He fully realizes that the domestic achievement gap "hurts the U.S. economically, exacerbates social divisions, and endangers our democratic society." We won't spoil his solution to the two-headed monster, but teachers who took offense to box office edu-drama Won't Back Down may need to exhale before reading.