"B is for Bubble" is a Sesame Street song performed by the kids and an adult male vocalist, over film footage of various kids chewing bubble gum and popping bubbles. The song is sung as a round, to the tune of "Three Blind Mice." Originally produced on 16mm film in 1969, the segment was made indoors with the kids blowing bubbles against a painted mural in the background. (First: Episode 0008) Ernie, Big Bird, the letter B, and some kids sang a short rendition of the song for a street scene in a 1999 episode.