In recent years, American public education has been swamped by bad ideas and policies. Our national leaders, most of whom were educated at elite universities and should know better, have turned our most important domestic duty into a quest for higher scores on standardized tests. While it is true that students must do well on standardized tests to enter universities, few of the better universities judge students’ knowledge and ability solely by such flimsy measures. Thus it is puzzling why public officials have made test scores the purpose of education.

The heavy reliance on standardized tests in schools began with the passage of George W. Bush’s No Child Left Behind legislation in 2001. The law mandated that every child in every school would take standardized tests in reading and math from grades three through eight and would achieve “proficiency” by the year 2014. No excuses. Even children who could not read English and children with significant cognitive handicaps would be expected to reach “proficiency.” Every state was left to define “proficiency” as it wished.

The punishments for not achieving higher test scores every year were increasingly onerous. A school that fell behind in the first year would be required to hire tutors. In the second year, it would have to offer its students the choice to move to a different school. By the end of five years, if it was not on track to achieve 100 percent proficiency, the school might be handed over to a private manager, turned into a charter school, taken over by the state, or closed. In fact, there was no evidence that any of these sanctions would lead to better schools or higher test scores, but no matter.

With these sanctions in mind, schools made intense efforts to prepare children to take the all-important tests. In some places, like Atlanta, Washington, D.C., and El Paso, Texas, teachers, principals, and superintendents cheated, changing the scores to save their jobs or their schools. Schools across the nation spent more time and money on preparing materials to help students pass tests and reduced the time for the arts, science, history, physical education, and even recess. Some states, such as New York and Illinois, manipulated the passing scores on the tests by lowering the definition of proficiency needed in order to demonstrate progress.

After Bush left office and was replaced by Barack Obama, the obsession with testing grew even more intense. Congress gave Secretary of Education Arne Duncan $5 billion in economic stimulus funds to encourage education reforms. Duncan released a plan…