Abstract
Renewed emphasis on increasing student academic achievement highlights the importance of improving educational quality despite limited educational budgets. This paper illustrates that investing in teachers' human capital has significant returns in the classroom. Using test and survey data on the educational background of teachers, we show that teacher knowledge and training have a significant impact on student performance and classroom productivity. Specifically, formal college-level instruction, learning by doing, and explicit measures of economic understanding all play important roles. Additionally, the data show that general in-service training is an imperfect substitute for formal education in economics. These results can be used to guide educational research, instructional programming, and school reform at the state and local levels.