Diane Ravitch is a leading education historian. Her work in that field is characteristically thorough and well-researched, and her books The Troubled Crusade and The Great School Wars, in particular, made significant contributions to our understanding of U.S. education history.

On the presumption that Ravitch is as much an expert on policy as she is on history, her latest book, recounting her change of heart on certain policy questions, has garnered enormous media attention. I suggest, with all due respect, that this presumption is a mistake. Unlike her thorough and rigorous historical writing, Ravitch’s policy opinions were never grounded in a systematic and comprehensive review of the relevant evidence. They should never have been given credence in the first place.

Consider Ravitch’s 1995 book National Standards in American Education, which endorsed the policy. When I was reviewing evidence on education standards for a chapter in my 1999 book Market Education, Ravitch’s book was still the preeminent source on the subject. After her historical work, it was a disappointment. Quoting Ravitch (p. 25), I wrote the following:

The most common claim made in support of government curricula is that: “Standards can improve academic achievement by clearly defining what is to be taught and what kind of performance is expected.” Unless readers are willing to accept this claim on faith, they can safely ignore it, because there is no compelling evidence that it is true. In her book National Standards in American Education, respected education historian and government standards advocate Diane Ravitch discusses many arguments pro and con, but does not demonstrate that government curriculum guidelines raise student achievement.

So far as I know, Ravitch never conducted a systematic review of the empirical evidence for national standards. Nor has she ever systematically and comprehensively reviewed the research comparing different kinds of public and private schools systems. She is not an authority on these matters.

If I’m mistaken on this point, I would appreciate a reference to any such works. If not, the media and policymakers would do well to stop according her opinions in these areas a weight they do not merit.