Teacher unions have played one of the most influenced roles not only in electoral campaigns of national and state politics, but also in every major sphere of educational policies in nation (Moe, 2009). More than changing these dynamics of policy making process, teacher unions are in the center of controversial issues since their statutory authority to negotiate with local school boards over collective bargaining agreements often result in rigid labor contracts, which limit administrative decision making.

The impact of teacher unions has been evaluated in several aspects such as teacher salaries, school spending and student performance over the last several decades (Eberts, 2007; Goldhaber, 2006; Stone, 2000; Hoxby, 1996; Eberts and Stone, 1984; West and Mykerezi, 2011; Strunk, 2011). A great volume of studies have found that teacher unions have done on increasing teacher salaries and school spending, but found little on student performance.

Since the principal product of collective bargaining, the collective bargaining agreement (or so called teacher contract) governs the relationship between public school teachers and public school employers, this covers a wide array of non-compensation related topics about teachers such as transfer, teacher evaluation and grievance procedures. However, limited studies exist on the relation between these different collective bargaining agreements and educational resources. This study fills a gap in past literature by using information about the collective bargaining agreement.

Using several main data set – multiple periods of teacher contracts from the State of New York Public Employee Relations Board (PERB), school resources and student performance from common core data, and teacher mobility from Personnel Master File (PMF) data - , this paper investigates whether educational resources such as teacher quality and teacher sorting are related with the extent of strictness in teacher contract. Furthermore, it extends the analysis to its impact on student performance.