This paper documents changes in the entire ability distribution of individuals entering the teaching profession using the 1979 and 1997 cohorts of the National Longitudinal Survey of Youth and a constructed Armed Force Qualifying Test score that allows direct comparison of ability between cohorts. Such direct comparison between cohorts was previously not possible due to a lack of directly comparable measures of ability. I find there are minimal differences in the ability distribution between cohorts. However, this similarity masks vast differences within specific demographics. I then also decompose these changes into cohort-wide shifts and within-cohort shifts of teachers.