The aim of "Sesame Street" was to build school preparedness and narrow the educational gap between lower- and upper-income children.

They used pedagogy advice from a Harvard professor. Research also showed children were more receptive when they watched with caregivers, so celebrities were introduced.

Music on "Sesame" functioned in three ways: As backing tracks for animation and film clips, as live performances by well-knows guest artists, and as songs for the human actors and Muppets to sing.

The belief was that as the characters were of different ethnicities, the music should be multicultural too. As "Sesame" became more popular, it pulled more major musical talent.

In 1973, Stevie Wonder participated in an episode-long musical guest, to teach Grover about vocal dynamics. Other stars also featured through the years, including Carly Simon, Diana Ross, Paul Simon, Billy Joel, and Celine Dion. There was also room for classical stars.

The message was that even world-famous stars could be accessible.

"Sesame" songs were built on a curriculum. Each year, outside experts outline pressing academic and social issues, and from that, an educational theme for the season is built.

After a song has lyrics, it is scored. Brevity and repetition are key, and the songs are tuned for catchiness. Demos go to producers and artists for approval and production suggestions.