Fifty years ago, with the Soviet Union's launch of the Sputnik satellite, millions of Americans found themselves peering anxiously into the night sky--and also looking inward, as they reconsidered previously cozy assumptions about their nation's technological and educational superiority. The 184-pound, unmanned aluminum beacon lasted just three months in orbit. But its legacy resonates to this day among U.S. educators and policymakers, who say lessons can be drawn from that Cold War-era milestone, even if they disagree on what those lessons are. Elected officials and business leaders continue to invoke Sputnik, which shot into space a half-century ago, in their calls to meet foreign economic competition by improving the skills of American students in mathematics, science, and other subjects. This article reports the lessons drawn from Sputnik and its impact on curriculum.