this seems false from my reading of TFA, though I didn't read the paper: > Identification is facilitated by variations across municipalities in the age distrib

this seems false from my reading of TFA, though I didn't read the paper: > Identification is facilitated by variations across municipalities in the age distribution of teachers at the time of quota removal, coupled with mandatory retirement at age 60. This means that students were differentially exposed to the newer post-quota cohorts, which had a different gender composition (fewer males) and a different distribution of scores on the matriculation exam (higher scores on average). the two groups were compared at the same time, but had different exposure to the post quota teacher cohort. this sounds like a great natural experiment. I'm also curious why you're so strongly a priori dismissing the benefits of male teachers.