Bewitched - Season 2 Episode 10
Junior Executive

A lesson is learned by watching this episode: if you want to appeal to kids, you have to be a kid yourself. Of course, Darrin learns that the hard way when he is changed into a boy courtesy of Endora. This turns out to be an excellent marketing ploy when Larry suggests that Darrin as a boy to promote his new clients toy ship company. Of course, Sam changes him back to an adult, but Larry and the client like the boy so much that Darrin gets changed back and forth from adult to kid!