If I Was a Cloud in the Sky

From Muppet Wiki

"If I Was a Cloud in the Sky" was sung by Mr. Snuffleupagus on Sesame Street. In the original sketch, Snuffy shows Big Bird the cloud costume he's going to wear in his Snufflegarten class's upcoming pageant about the sky, and even sings the song that accompanies it, while Big Bird imagines him as a cloud.

In Episode 4088, Snuffy sang this song again as he had balloons tied around him to get him to float into the sky.