Editor’s note: This segment was rebroadcast on Sept. 30, 2025. Click here for that audio. In the early 2000s, thousands of U.S. schools had their students race the clock to stack cups in gym class.

Yung-Deng Lin can stack a group of cups in about 1.6 seconds, an impressive time for a 7-year-old. To give an idea of how fast the child can stack cups, the World Sport Stacking Association overall ...

Clack-clack-clack-clack. Like the hoof beats of a thousand baby Clydesdales. This is cup stacking, the deceptively simple task of building and taking down pyramids of plastic cups. Fast. How fast? All ...