Original format and format

Format
Original format

From the first episode, Sesame Street's producers have used "different elements" of commercial television: "a strong visual style, fast-moving action, humor, and music". They also used videotaped spots, puppets, animation, live action, and music. Cooney was the first to suggest that they use "teaching commercials", or several twelve -to ninety-second shorts, and the repetition of several key concepts throughout an episode.[18]

The producers and writers decided to build the new show around a brownstone or an inner-city street, a choice that was "unprecedented".[10] They wanted to attract inner-city viewers, so they reproduced these viewers' neighborhoods as its setting—a realistic city street, complete with peeling paint, alleys, front stoops, and metal trash cans along the sidewalk".[19] The cast needed to reflect the diversity of this kind of neighborhood, first with a mix of White and African-American actors, and then with Hispanics and Asians later on. Sesame Street was also the first children's show to utilize research as a production value. It addressed specific curriculum and goals for its preschool audience and used research to "inform production".[3] The research team designated a "curriculum focus" every season, and identified and emphasized a "small set of related objectives" that were written into each episode.[20]
Hal Miller, who played Gordon from 1971-1973, and Loretta Long (Susan), with Oscar the Grouch (Carroll Spinney). Sesame Street is a fully integrated television show: The producers, early in the show's history, decided to eschew the advice of experts and allow Muppets and humans to interact.

In addition, the researchers and producers made use of repetition and reinforcement throughout the show's segments. The format remained the same from episode to episode, but the content was varied so that new concepts could be introduced.[21] The show was designed to encourage "coviewing" with the use of humor, which was written into the show so that children and their parents could appreciate it together.[22] Cultural references were used, which included bringing celebrities to appear on it, that only adults would understand.[23] Music was also used, since as Cooney observed, children have an "affinity for commercial jingles".[24]

When Sesame Street premiered, research about children's viewing habits assumed that they did not have long attention spans. As a result, each episode was structured like a magazine. They presented a story, dispersed throughout the hour-long show, broken up with segments, or skits, which usually totaled approximately forty each episode. Although the story, which occurred during what the producers called "the street scenes", usually lasted about ten-to-twelve minutes in length, it would take forty-five minutes to tell it.[25][26][note 3] It was decided, by recommendation of child psychologists, that the Street scenes, which CTW researcher Edward Palmer called "the glue" that "pulled the show together",[27] would never feature the human actors and Muppets together because they were concerned it would confuse and mislead young children.[28]

Before the show's premiere, the producers created five one-hour episodes for the purpose of testing whether children found them comprehensible and appealing. They were never intended for broadcast. Instead, they were presented to preschoolers in 60 homes throughout Philadelphia in July 1969. The results were "generally very positive",[28] but they found that although children attended to the shows during the Muppet segments, their interest was lost during the "Street" segments. As a result, the appeal of the test episodes were lower than they preferred,[29] so significant changes were made. CTW researcher Gerald Lesser called their decision to defy the recommendations of their advisers "a turning point in the history of Sesame Street".[27] The producers went back and reshot the Street segments; Henson and his team created Muppets that could interact with the human actors,[27][30] specifically "two of Sesame Street's most enduring Muppets: Oscar the Grouch and Big Bird".[31] These test episodes were directly responsible for what writer Malcolm Gladwell calls "the essence of Sesame Street--the artful blend of fluffy monsters and earnest adults".[27]
Michael Jeter (in 1992), who played "Mr. Noodle's brother Mr. Noodle" in the "Elmo's World" segment of Sesame Street until his death in 2003.
Format changes of the 1990s and 2000s

Sesame Street's format remained intact until the show's later decades. By the 1990s, its dominance was challenged by other programs, and its ratings declined. New research, the growth of the children's home video industry, and the increase of thirty-minute children's shows on cable demonstrated that the traditional magazine-format was not necessarily the most effective way to hold their attention.[32] For Sesame Street's 30th anniversary in 1999, its producers researched the reasons for the show's lower ratings. For the first time since the show debuted, the producers and a team of researchers analyzed Sesame Street's content and structure during a series of two-week long workshops. They also studied how children's viewing habits had changed in thirty years. They found that although the show was produced for three to five year olds, children began watching it at a younger age. As a result, the target age for Sesame Street shifted downward, from four years to three years.

In 1999, a 15-minute long segment that targeted the developmental age of the show's newer viewers began to be shown at the end of each episode. The segment, called "Elmo's World", used traditional elements (animation, Muppets, music, and live-action film), but had a more sustained narrative,[33] followed the same structure each episode, and depended heavily on repetition. Unlike the realism of the rest of the show, "Elmo's World" took place in a stylized crayon-drawing universe as conceived by its host.[34] Elmo, who represented the younger audience, was chosen as the host of the closing segment because younger toddlers identified with him[35] and because he had always tested well with them.[36][note 4]

In 2002, Sesame Street's producers went further in changing the show to reflect its younger demographic. They decided, after the show's 33rd season, to expand upon the "Elmo's World" concept by "deconstructing"[37] the show. They changed the structure of the entire show to a more narrative format, making the show easier for young children to navigate. Arlene Sherman, a co-executive producer for 25 years, called the show's new look "startlingly different".[37]