The Yeshiva decided to field a rowing team. Unfortunately, they lost race after race. They practiced for hours every day but never managed to come in any better than dead last.
The Rosh Yeshiva (the Yeshiva head) finally decided to send Yankel to spy on the Harvard team. So Yankel schlepped off to Cambridge and hid in the bulrushes of the Charles River, from where he carefully watched the Harvard team as they practiced.
Yankel returned to Yeshiva, and announced: "I have figured out their secret."
"What? Tell us," they all wanted to know.
"We should have eight guys rowing and only one guy shouting."