Title: The narrowing gap in New York City teacher qualifications and its implications for student achievement in high-poverty schools
Description: "The gap between the qualifications of New York City teachers in high-poverty schools and low-poverty schools has narrowed substantially since 2000.  Most of this gap-narrowing resulted from changes in the characteristics of newly hired teachers, and largely has been driven by the virtual elimination of newly hired uncertified teachers coupled with an influx of teachers with strong academic backgrounds in the Teaching Fellows program and Teach for America.  The improvements in teacher qualifications, especially among the poorest schools, appear to have resulted in improved student achievement.  By estimating the effect of teacher attributes using a value-added model, the analyses in this paper predict that observable qualifications of teachers resulted in average improved achievement for students in the poorest decile of schools of .03 standard deviations, about half the difference between being taught by a first year teacher and a more experienced teacher.  If limited to teachers who are in the first or second year of teaching, where changes in qualifications are greatest, the gain equals two-thirds of the first-year experience effect"--National Bureau of Economic Research web site.