American public education, a perennial whipping boy for both the political right and left, is once again making news in ways that show how difficult it will be to cure what ails the nation’s schools. Only last week, President Obama declared that every high school graduate must be fully prepared for college or a job (who knew?) and called for significant changes in the No Child Left Behind law. In Kansas City, Mo., officials voted to close nearly half the public schools there to save money. And the Texas Board of Education approved a new social studies curriculum playing down...