<P> The preschool educational television program Sesame Street was first aired on public broadcasting television stations November 10, 1969, and will reach its 47th season in 2017 . The history of Sesame Street has reflected changing attitudes to developmental psychology, early childhood education and cultural diversity . Featuring Jim Henson's Muppets, animation, live shorts, humor and celebrity appearances, it was the first television program of its kind to base its content and production values on laboratory and formative research, and the first to include a curriculum "detailed or stated in terms of measurable outcomes". Initial responses to the show included adulatory reviews, some controversy and high ratings . By its 40th anniversary in 2009, Sesame Street was broadcast in over 120 countries, and 20 independent international versions had been produced . </P> <P> The show was conceived in 1966 during discussions between television producer Joan Ganz Cooney and Carnegie Corporation vice president Lloyd Morrisett . Their goal was to create a children's television show that would "master the addictive qualities of television and do something good with them", such as helping young children prepare for school . After two years of research, the newly formed Children's Television Workshop (CTW) received a combined grant of $8 million from the Carnegie Corporation, the Ford Foundation and the U.S. federal government to create and produce a new children's television show . </P> <P> By the show's tenth anniversary in 1979, nine million American children under the age of six were watching Sesame Street daily, and several studies showed it was having a positive educational impact . The cast and crew expanded during this time, including the hiring of women in the crew and additional minorities in the cast . In 1981, the federal government withdrew its funding, so the CTW turned to other sources, such as its magazine division, book royalties, product licensing and foreign income . During the 1980s, Sesame Street's curriculum expanded to include topics such as relationships, ethics and emotions . Many of the show's storylines were taken from the experiences of its writing staff, cast and crew, most notably the death of Will Lee--who played Mr. Hooper--and the marriage of Luis and Maria . </P>

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