"Sing" is a 1971 song written by Joe Raposo for the children's television show Sesame Street. In 1973, the song gained popularity when performed by the Carpenters, who made it a #3 hit on the Billboard Hot 100.

Raposo was one of the staff songwriters on Sesame Street, and the song became one of the most popular on the program, sung in English, Spanish, and sign language. In its initial appearance, the song was sung by adult human cast members of the show (the most frequent lead singer was Bob McGrath) and Muppets, including Big Bird.

Barbra Streisand's 1972 version of "Sing" was released as a single, reaching number 28 on the Easy Listening chart and number 98 on the Billboard Hot 100. Many other versions of the song have since been recorded by a variety of artists including Trini Lopez who recorded a Spanish language version in 1972 which appeared on his album, "Viva" (1972).

Although Barbra Streisand had an Easy Listening hit in 1972 with "Sing", Karen and Richard Carpenter heard the song for the first time as guests on ABC television special Robert Young with the Young in 1973. The Carpenters loved the song and felt it could be a hit. The song acted as their debut single from the LP album Now & Then, released in 1973. "Sing" reached number three on the Billboard Hot 100 chart and number-one on the easy listening chart, and it became the group's seventh gold single.

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