"Polka Dots and Moonbeams" is a popular song with music by Jimmy Van Heusen and lyrics by Johnny Burke, published in 1940. It was Frank Sinatra's first hit recorded with the Tommy Dorsey Orchestra.
In this version it's arranged for a ballet class "rond de jambe à terre" exercises and played by Peter James on his album "Music for Ballet Class - MORE Songs from the 1940s"
For more info about the album click here: https://bit.ly/3uaJza1