No country for young kids? The effects of school starting age throughout childhood and beyond

Being the youngest in a cohort entails many penalties. Using administrativedata of every public-school student in Portugal, we show that although performancegains from being 1-year older fade quickly from primary education to high school,age-related penalties persist through a combination of grade retention, educationaltracking and testing policies. Those that start school younger are more likely torepeat grades and ultimately drop out from school. Older entrants are more likelyto enroll in scientific curricula in high school, are more successful at accessing publichigher education and enroll in more selective undergraduate courses