 It began in 1990 with 500 teachers and has since expanded to over 4,000 teacher placements in 2010.In the Journal of Policy Analysis and Management they use individual-level student data linked to teacher data in North Carolina to estimate the effects of having a TFA teacher compared to a traditional teacher.According to studies about the effect of different teacher-preparation programs in Louisiana, North Carolina, and Tennessee, TFA is among the most effective sources of new teachers in low-income communities.