Family and social networks are widely believed to influence important life decisions but identifying their causal effects is notoriously difficult. Using admissions thresholds that directly affect older but not younger siblings' college options, we present evidence from the United States,...

Only half of SAT-takers retake the exam, with even lower retake rates among low income and underrepresented minority (URM) students. We exploit discontinuous jumps in retake probabilities at multiples of 100, driven by left-digit bias, to estimate retaking's causal effects. Retaking...

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...