1. News Anchor Anderson Cooper with Elmo at the 6th Annual Sesame Workshop Benefit Gala on May 28, 2008 in New York City. Anderson Cooper also filled in for Oscar the Grouch on Sesame Street, reporting on news for GNN (Grouch News Network) back in 2007.
3. Gray’s Anatomy’s Chandra Wilson gives Sesame Street’s Elmo a squeeze!
PHOTOS: Celebs who have appeared on Sesame Street
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 News Anchor Anderson Cooper with Elmo at the 6th Annual Sesame Workshop Benefit Gala on May 28, 2008 in New York City. Anderson Cooper also filled in for Oscar the Grouch on Sesame Street, reporting on news for GNN (Grouch News Network) back in 2007. Photo: Getty Images
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 NBC’s Brian Williams with Elmo and Leela on Sesame Street. Photo: Courtesy of Richard Termine/PBS
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 Gray’s Anatomy’s Chandra Wilson gives Sesame Street’s Elmo a squeeze! Photo: Courtesy of Jesse Grant/PBS
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 International soccer sensation and the LA Galaxy’s super star, David Beckham, demonstrates and describes the meaning of the word “persistent” with Sesame Street’s Elmo as part of the show’s 39th season. Photo: Courtesy of Jesse Grant/PBS
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 Project Runway host and supermodel Heidi Klum strikes a pose with Sesame Street’s Elmo and together they define the word “compliment” as part of the 39th season. Photo: Courtesy of Jesse Grant/PBS
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 Comedian and actor, Jack Black, gets friendly with Sesame Street’s Elmo. Photo: Courtesy of Jesse Grant/PBS
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 Miami Dolphins star Jason Taylor helps Elmo define the word “toss” as part of Sesame Street’s 39th season. Photo: Courtesy of Jesse Grant/PBS
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 Jenny McCarthy strikes her best “insect” pose as she defines the meaning of the word “insect” with Sesame Street’s Elmo and what else? An insect! Photo: Courtesy of Jesse Grant/PBS
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 Jessica Alba visits with Sesame Street’s Elmo and defines the word “scrumptious.” Photo: Courtesy of Jesse Grant/PBS
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 Jessie, Katie Couric and Elmo help families cope with the death of a parent. Photo: Courtesy of Philippe Cheng/PBS
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 Katy Perry’s appearance on an upcoming Sesame Street episode was cut by the show, allegedly because of the level of cleavage on display. Photo: WENN
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 Actor and musician, LL Cool J sings the “Addition Expedition” song with Sesame Street’s Elmo. Photo: Courtesy of Richard Termine/PBS
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 Dirty Job’s Mike Rowe visits Oscar who has him do the dirtiest jobs on Sesame Street. Photo: Courtesy of Richard Termine/PBS
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 Molly Shannon helps Oscar’s pet worm Slimey adopt a bug as part of Sesame Street’s 39th Season. Photo: Courtesy of Richard Termine/PBS
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 American Idol’s Randy Jackson smiles with his favorite furry red Muppet, Sesame Street’s Elmo. Photo: Courtesy of Jesse Grant/PBS
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 Comedian Ricky Gervais sings Elmo a lullaby as part of Sesame Street’s 40th season. Photo: Courtesy of Richard Termine/PBS
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 30 Rock’s Will Arnett as Max the Magician with Sesame Street’s Rosita, Chris, Big Bird and Elmo. Photo: Courtesy of Richard Termine/PBS
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