Traditionally, states have required individuals complete a program of study in a university-based teacher preparation program in order to be licensed to teach. In recent years, however, various "alternative certification" programs have been developed and the number of teachers obtaining teaching certificates through routes other than completing a traditional teacher preparation program has skyrocketed. In this paper I use a rich longitudinal data base from Florida to compare the characteristics of alternatively certified teachers with their traditionally prepared colleagues. I then analyze the relative effectiveness of teachers who enter the profession through different pathways by estimating "value-added" models of student achievement. In general, alternatively certified teachers have stronger pre-service qualifications than do traditionally prepared teachers, with the least restrictive alternative attracting the most qualified perspective teachers. These differences are less pronounced when controlling for the grade level of teachers, however. On average, alternatively certified science teachers have also had much more coursework in science while in college than traditionally prepared science teachers. The same is not true for math teachers, where the hours of college coursework are approximately equal across pathways. Of the three alternative certification pathways studied, teachers who enter through the path requiring no coursework have substantially greater effects on student achievement than do either traditionally prepared teachers or alternative programs that require some formal coursework in education. These results suggest that the additional education coursework required in traditional teacher preparation programs either does little to boost the human capital of teachers or that whatever gains accrue from traditional teacher education training are offset by greater innate ability of individuals who enter teaching through routes requiring little formal training in education. (Contains 7 tables and 13 footnotes.)