Education policy, like so many areas of lawmaking, is rife with reform proposals that, while attractive on paper, are supported by little or no evidence. Some are even proven failures. Yet once a lawmaker becomes fixated on a proposal, it seems that no amount of evidence will dampen that pursuit, and recent years have provided no shortage of evidence-free fixations: charter schools, cyberschools, private school vouchers, teacher merit pay, evaluation of teachers based on students' test scores and -- most recently and most persistently -- grade retention policies that require students to repeat a year in school.
Let's look at grade retention. States across the U.S. are adopting mandates requiring that third graders with low reading scores repeat the grade. But retaining students is not a new idea. It's an experiment that has been tried on and off for generations, and it's been studied for almost that long.
The overarching message from research in this area is that retaining a low-scoring third grader will not help her do better than a similar classmate with similar scores who is moved along to fourth grade -- but she will be more likely to eventually drop out.