Almost all countries worldwide closed schools at the outbreak of the Covid-19 crisis. I document that schooling time dropped on average by -55% in the US and -45% in Germany from the onset of the crisis to the summer of 2021. In the US, schools were closed longer in richer than in poorer areas,...

We provide evidence that the robust association between cognitive skills and economic growth reflects a causal effect of cognitive skills and supports the economic benefits of effective school policy. We develop a new common metric that allows tracking student achievement across countries, over...