That's why sketches often have contemporary celebrity guests or pop culture references that 2-year-olds don't get, but adults do. A James Bond parody stars Cookie Monster as a secret agent, Double-Stuffed 7, in The Spy Who Loved Cookies. Another show celebrates "what makes people special", with Elmo telling Lupita Nyong'o that her skin "is a beautiful brown color". The actress responds, "Skin comes in lots of beautiful shades and colors ... I love my skin!" It's a classic Sesame Street lesson about diversity that goes back to its groundbreaking roots as one of the few shows in the 1970s to feature all races and ethnicities. Today the show also routinely features children with disabilities.

Newer seasons also feature less of the actual street with human characters, and more puppets in skits with animation or other technical wizardry. Executive producer Carol-Lynn Parente says the puppets "have a madcap energy to them" that helps Sesame Street compete with the many other kids' shows that are animated.

Sesame Street also is unique because before any scripts are written, child-development experts offer input on what today's kids need to succeed in school. That's why in addition to teaching letters, numbers and values, the show now teaches behaviors like impulse control and listening to directions.

"Cookie Monster has been our poster child for self-regulation because of his love of cookies," says Parente. The puppet sometimes now eats fruits and vegetables instead - although he may also devour the plate, table and chair.

Some of today's parents say Sesame Street has lost its relevance.

But Lori Chajet of Brooklyn, New York, says her daughters, 7 and 10, loved it - including old episodes they got on tape - while she and her husband appreciated the emphasis on multiculturalism and the pop culture references for adults.

"Little kids learn from it," says her 7-year-old daughter Sasha, "but they really have a really fun time watching it."

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