For the past 29 years, NBC has devoted a portion of airtime that could otherwise be sold for substantial advertising dollars to provide brief reminders about basic human decency, teen issues, and social controversies. Efficiently packaged in 30-second increments and featuring recognizable faces, The More You Know campaign has become synonymous with lessons in ethics. Wrap up a serious conversation with your kid about drug use and they’re likely to respond by humming the campaign’s theme song. (“Da-da-da-dahhh.”)

But how did the network find itself the messenger for these widely celebrated (and widely parodied) spots? And did they really have any impact?

 
 

The idea of a public service announcement—a philanthropic use of airtime on television or radio to serve a greater good—started in the United States back in the 1940s, when stations allocated some of their commercial or program time to remind people about the war efforts under the guidance of the newly-formed War Advertising Council. The idea had been imported from the UK, which had long featured film reels on public safety tips, like how to cross a road. PSAs relied on truncated, catchy messages (“Loose lips sink ships”) to impart ideas with the limited time they had available.

After the Allied victory, the War Advertising Council became the Ad Council, and the scope of their mission changed from world-altering events to comparatively mundane topics. Aligned with mandates from the Federal Communications Commission (FCC), public service announcements attempted to balance special interests with objective information. In the late 1960s, for example, the FCC’s Fairness Doctrine took aim at tobacco advertising, with one PSA on the dangers of the habit airing for every three cigarette spots. The number of smokers in the U.S. actually declined before the FCC banned such advertising from airwaves altogether in 1971.

By the 1980s, the major networks (ABC, NBC, CBS) narrowed their PSA efforts by giving them a unique identity. ABC’s Schoolhouse Rock was among the most popular, using catchy songs to illustrate points about government or science. NBC aired One to Grow On, a series of cautionary messages about everything from chewing tobacco to finishing your homework, with Mr. T. and Michael J. Fox sharing their scripted wisdom.

 
 

In the late 1980s, Rosalyn Weinman, NBC's vice president of broadcast standards and practices, was approached by several nonprofit educational groups to see if the network might want to get involved in raising awareness for the teacher shortage affecting the country. Weinman reached out to former NBC creative director-turned-ad executive Steve Lance, gave him a slogan (“The More You Know”), and asked him to produce five test spots centered around the importance of teachers and education. While NBC wasn't crazy about the campaign, Weinman had support from her own team and from some marketable names working for the network.

“She said she had a few stars of NBC series willing to do PSAs. What I absolutely didn’t want to do was a talking-head campaign," Lance tells Mental Floss of not wanting to shoot videos where actors would stand or sit on a spare set and deliver their message. "Talking heads were absolute death.”

Instead, Lance wrote a series of spots focusing on bolstering the public perception of teachers by acknowledging famous educators throughout history like Aristotle and Albert Einstein and stretching Weinman’s slogan to “The more you know, the more you can teach.” Miami Vice co-star Saundra Santiago appeared in one of the spots, which began airing in 1989; so did news anchors Tom Brokaw and Deborah Norville, as well as L.A. Law co-stars Michael Tucker and Jill Eikenberry.

To help give the campaign a visual identity, Lance was paired with Steve Bernstein, a graphic designer who came up with the shooting star illustration that signaled the end of the segment. Bernstein tells Mental Floss he wondered why NBC was reaching out to freelancers rather than in-house employees. "Nobody else [at NBC] would do it," he says. "They were too busy, so Rosalyn had to go outside the network." Bernstein came up with a star that fit neatly under the "W" in the slogan.

Originally, the logo was filmed so it looked like it was in motion, not animated. “We didn’t have the budget for that,” Lance says. The familiar melody was composed by two-time Emmy winner Michael Karp, who also created the theme for Dateline NBC.

The spots garnered praise: Lance wrote a total of 17 that first year, all of them centered around the importance of educators—but Lance left after finishing that first batch when Weinman decided to go in a different direction: NBC was apparently concerned viewers wouldn’t be able to tell the difference between set-decorated spots and actual commercials, so Weinman reverted to the “talking head” premise.

 
 

Despite Lance's departure and the change of format, the series continued just as successfully as before. Its minimalist approach was attractive to actors who enjoyed delivering their lines in a loose and informal setting, and by 1996, director David Cornell herded in actors (including Courteney Cox, Jonathan Silverman, and Eriq La Salle) over a single weekend to tape spots for the entire year, often asking them to pare down their delivery so that it would fit into a 25-second block of time. (The last five seconds were reserved for the star graphic and Karp’s melody.)

The Ad Council, which had seen its role minimized over the years, would later take issue with the proprietary campaigns launched by networks, arguing that they were little more than stealth ads for their programs. To their point, NBC did appear to use at least half the casts of ER and Seinfeld. But the spots could sometimes net tangible results: In 1995, after a series of The More You Know spots on domestic violence, calls to the Domestic Violence Hotline went from 228 calls daily to quadruple that amount. The network earned a Public and Community Service Emmy for its efforts, and the campaign—which still airs on NBC—grew to include spots by the cast of Friends and a comedic take courtesy of The Office, as well as appearances by sitting presidents Bill Clinton and Barack Obama. You can watch some of the more well-known (and rather dated) spots below.