Holding a college major in education is not correlated with effectiveness in elementary and middle school classrooms, regardless of the university at which the major was earned. Teachers do become more effective with a few years of teaching experience, but (except in elementary reading) no gains--and some declines--in effectiveness appear in the second decade after a teacher has begun teaching. These and other results are obtained from estimations using value-added models that control for student characteristics as well as school and (where appropriate teacher) fixed effects that estimate teacher effectiveness in reading and math for Florida students in 4th through 8th grades for six school years, 2001-02 through 2006-07. The findings suggest that teacher selection and compensation policies are in need of revision. (Contains 2 figures, 11 tables and 13 footnotes.) [This paper was prepared for the PEPG Conference "Merit Pay: Will It Work? Is It Politically Viable?"]