This was the legacy of Sesame Street: If you paid careful attention to the structure and format of your material, you could dramatically enhance stickiness. But is it possible to make a show even stickier than Sesame Street? This was what three young television producers at the Nickelodeon Network in Manhattan asked themselves in the mid-1990s. It was a reasonable question. Sesame Street, after all, was a product of the 1960s, and in the intervening three decades major strides had been made in understanding how children's minds work. One of the Nickelodeon producers, Todd Kessler, had actually worked on SesameStreet and left the show dissatisfied. He didn't like the fast-paced "magazine" format of the show. "I love SesameStreet," he says. "But I always believed that kids didn't have short attention spans that they could easily sit still for a half an hour." He found traditional children's television too static. "Because the audience is not all that verbal or even preverbal, it is important to tell the story visually," he went on. "It's a visual medium, and to make it sink in, to make it powerful, you've got to make use of that. There is so much children's television that is all talk. The audience has a hard time keeping up with that." Kessler's colleague, Tracy Santomero, grew up on Sesame Street and had similar misgivings. "We wanted to learn from SesameStreet and take it one step further," Santomero said. "TV is a great medium for education. But people up until now haven't explored the potential of it. They've been using it in a rote way. I believed we could turn that around."

What they came up with is a show called Blue's Clues. It is half an hour, not an hour. It doesn't have an ensemble cast. It has just one live actor, Steve, a fresh-faced man in his early twenties in khakis and a rugby shirt who acts as the show's host. Instead of a varied, magazine formal, each episode follows a single story line — the exploits of an animated dog by the name of Blue. It has a flat, two-dimensional feel, more like a video version of a picture book than a television show. The pace is deliberate. The script is punctuated with excruciatingly long pauses. There is none of the humor or wordplay or cleverness that characterizes Sesame Street. One of the animated characters on the show, a mailbox, is called Mailbox. Two other regular characters, a shovel and a pail, are called Shovel and Pail. And Blue, of course, the show's star, is Blue because he's the color blue. It is difficult, as an adult, to watch Blue's Clues and not wonder how this show could ever represent an improvement over Sesame Street. And yet it does. Within months of its debut in 1996, Blue'sClues was trouncing Sesame Street in the ratings. On the Distracter test, it scores higher than its rival in capturing children's attention. Jennings Bryant, an educational researcher at the University of Alabama, conducted a study of 120 children, comparing the performance of regular Blue's Clues watchers to watchers of other educational shows on a series of cognitive tests.

"After six months we began to get very big differences," Bryant said. "By almost all of our measures of flexible thinking and problem solving, we had statistically significant differences. If there were sixty items on the test, you might find that the Blue's Clues watchers were correctly identifying fifty of them, and the control group was identifying thirty-five." Blue's Clues may be one of the stickiest television shows ever made.

How is it that such an unprepossessing show is even stickier than Sesame Street? The answer is that SesameStreet, as good as it is, has a number of subtle but not insignificant limitations. Consider, for example, the problem created by the show's insistence on being clever. From the beginning Sesame Street was intended to appeal to both children and adults. The idea was that one of the big obstacles facing children — particularly children from lower-income families — were that their parents didn't encourage or participate in their education. Sesame Street's creators wanted a show that mothers would watch along with their children. That's why the show is loaded with so many "adult" elements, the constant punning and pop culture references like Monsterpiece Theater or the Samuel Beckett parody "Waiting for Elmo." (The show's head writer, Lou Berger, says that the reason he applied for a job at SesameStreet was because of a Kermit sketch he saw while watching the show with his son in 1979. "It was one of those crazy fairy tales. They were looking for a princess in distress. Kermit ran out to this female Muppet princess and said" — and here Berger did a pitch-perfect Kermit — "'Excuse me, are you a female princess in distress?' And she said, 'What does this look like? A pant suit?' I remember thinking, 'That's so great. I have to work there.'")

The problem is, preschoolers don't get these kinds of jokes, and the presence of the humor — like the elaborate pun on "distress" — can serve as a distraction. There is a good example of this in an episode of Sesame Street called "Roy" that ran on Christmas Eve in 1997. The episode opens with Big Bird running into a mail carrier, who has never been on Sesame Street before. The mail carrier hands Big Bird a package, and Big Bird is immediately puzzled: "If this is the first time you have ever been here," he asks, "how did you know I was Big Bird?"

MAIL CARRIER: Well, you have to admit, it's easy to figure out! [Gestures broadly at Big Bird]

BB: It is? [Looks at himself]. Oh, I see. The package is for Big Bird, and I'm a big bird. I forget sometimes. I'm just what my name says. Big Bird is a big bird.

Big Bird becomes sad. He realizes that everyone else has a name — like Oscar, or Snuffy — but he has only a description. He asks the mail carrier what her name is. She says Imogene.

BB: Gee, that's a nice name. [Looking to the camera, wistfully] I wish I had a real name like that, instead of one that just says what I am, as if I were an apple or a chair or something."

Thereupon begins a search by Big Bird for a new name. With the help of Snuffy, he canvases Sesame Street for suggestions — Zackledackle, Butch, Bill, Omar, Larry, Sammy, Ebenezer, Jim, Napoleon, Lancelot, Rocky — before settling on Roy. But then, once everyone starts calling him by his new name. Big Bird realizes that he doesn't like it after all. "Somehow it doesn't seem right," he says. "I think I made a big mistake." He switches back. "Even if Big Bird isn't a regular name," he concludes, "it's my name, and I like the way all my friends say it."

This was, at least on the surface, an excellent episode. The premise is challenging and conceptual, but fascinating. It deals candidly with emotion, and, unlike other children's shows, tells children that it's okay not to be happy all of the time. Most of all, it's funny.

It sounds like it should be a winner, right?

Wrong. The Roy show was tested by the Sesame Street research staff and the numbers were very disappointing. The first segment involving Snuffy and Big Bird did well. As you would expect, the viewers were curious. Then things began to fall apart. By the second of the street scenes, attention dropped to 80 percent. By the third, 78 percent. By the fourth 40 percent, then 50, then 20. Alter viewing the show, the kids were quizzed on what they had seen. "We asked very specific questions and were looking for clear answers," Rosemary Truglio, SesameStreet's research head said. "What was the show about? Sixty percent knew. What did Big Bird want to do? Fifty three percent knew. What was Big Bird's new name? Twenty percent knew. How did Big Bird feel at the end? Fifty percent knew." By comparison, another of the shows tested by Sesame Street at the very same time recorded 90 percent plus correct answers on the postshow quiz. The show simply wasn't making any impression. It wasn't sticking.