10.2190/CUNW-P5M3-YAKE-J9TD CUNWP5M3YAKEJ9TD 0 THE LINKAGES BETWEEN TEACHER UNIONS AND STUDENT ACHIEVEMENT 20020509 20020509 20020509 20020509 CUNWP5M3YAKEJ9TD.pdf http://baywood.metapress.com/link.asp?target=contribution&id=CUNWP5M3YAKEJ9TD 4 MICHAEL A. ZIGARELLI Over the past decade, researchers have uncovered a positive teacher union productivity effect in the public schools and have further demonstrated that the benefits of unionized schooling accrue primarily to the average student, possibly at the expense of other students. At present, however, the moderators of the union-achievement relationship have not been definitively identified. After surveying literature from the fields of education, industrial relations, and organizational theory, a model of how teacher unions influence student achievement was constructed and tested. The teacher union productivity effect was found to be primarily generated by organizational changes in response to unionization rather than by specific union bargaining gains.