The Big Bang Theory Season 1 Episode 13
The Bat Jar Conjecture
The guys compete in a physics bowl after the previous contestants dropped out to form a barbershop quartet. When Sheldon's showboating becomes too much for them, they kick him off the team. An upset Sheldon forms his own team to compete against them which includes the third floor janitor, the lunch lady and her son. The other boys, meanwhile, grab Leslie Winkle as their fourth.
At the bowl, the guys call themselves PMS (Perpetual Motion Squad) and Sheldon's team is AA (Army Ants). PMS wins by one question when Sheldon is unable to answer the final he won't allow the janitor to state the answer even though he knows it. Penny then does her own test to see who's the smartest by asking pop culture questions. Neither boy is able to answer any question.