We demonstrate that heat inhibits learning and that school air-conditioning mitigates this effect. Student fixed effects models using 10 million PSAT-retakers show hotter school days in years before the test reduce scores, with extreme heat being particularly damaging. Weekend and summer heat...

We study within-family spillovers in college enrollment to show college-going behavior is transmissible between peers. Because siblings' test scores are weakly correlated, we exploit college-specific admissions thresholds that directly affect older but not younger siblings' college options....