Factual error: In the episode, "Professor Blackjack", Manny puts a stack of one hundred dollar bills on the card table for the professor to bet. The bills are the new ones issued a few years ago with the enlarged portrait of Benjamin Franklin. The scene is supposed to take place in 1961.
Factual error: In the episode "Gadget Gamblers" when the engineer and his family are partying with the professional gamblers, a stack of $100 bills can be seen on the coffee table. The bills are the new ones first issued a few years ago, that have the enlarged portrait of Benjamin Franklin, but the scene is supposed to take place in 1972.