U.S. youths score lowest on U.S. history among all disciplines, according to the National Assessment of Educational Progress survey released last week. A distressing 2 percent of high school seniors knew what Brown v. Board of Education was about. Civic apathy is nothing new, but the reports are increasingly dire.

Since the passage of the No Child Left Behind legislation, states and school districts have focused intensely on raising scores in math and reading, too often at the expense of social studies — something Education Secretary Arne Duncan has acknowledged. Overall, only 12 percent of this year’s tested batch were deemed proficient, while the majority of students scored at “a below basic” achievement level. Only one in 10 knew the constitutional tenets of checks and balances and separation...