On top of many policymakers' wish lists is increased teacher pay. Particular attention also has focused on mechanisms such as merit pay to target rewards to the most effective teachers and keep them in the classroom. Yet resources are constrained. Raising pay for some or all teachers inevitably takes funds away from some other element of…

Beginning this year with its 2012 graduating class, the University of Notre Dame ended its practice of offering diplomas made of sheep's skin, a tradition that has all but disappeared except in some stubborn corners of academia. But the tendency of employers to pay premiums to workers holding certain diplomas is thriving. This tendency, dubbed the…