The now famous opening number "I Feel Pretty" was first performed on the 1973 special "Julie on Sesame Street" starring Julie Andrews and Perry Como. The character "changes" are much more smooth three years later. In the Muppet Show version Beautiful Day Monster arrives at the door while on the 1973 Sesame Street version, Frazzle is waiting for his beauty! Before Charles tries his French experiment in the talk spot, he asks Kermit if Piggy speaks any French to which he replies she doesn't speak a word - although Piggy's demonstrated her use of the word "moi" two episodes ago. In later seasons, her vocabulary would be peppered with more French. This isn't too much of a contradiction though as this episode takes place before any of Piggy's French speaking, excepting her use of "moi" which she could have easily picked up anywhere without knowing any other words. Even in later seasons, Piggy's mastery of the language is questioned, most notably in the Elke Sommer and Jean Pierre-Rampal episodes, implying that while Piggy has mastered a few select words/phrases, she doesn't know enough to pass a French 101 exam.