Schoolhouse Rock! c. 1973 : Animated education takes off

Schoolhouse Rock! was born on the first Saturday in 1973 with this short, which established the sensibility of one of the most significant works of educational animation in modern history. Co-created by a team from an ad agency, including Thomas Yohe, who provided the drawings that became the basis for the animation, “Three Is a Magic Number” was written and performed by jazz musician Bob Dorough, who would go on to contribute to 32 more memorable Schoolhouse Rock! efforts.

“Three Is a Magic Number” was a catchy song, effective at cementing multiplication tables in children’s heads, and moving in its evocation of holy trinities, triangles, and single-child families. The animation was just as elegant in its simplicity. Combined, the music and those visuals created a distinctive aesthetic that would be expanded upon in “Conjunction Junction,” “I’m Just a Bill,” and many other shorts, which were shown regularly between commercials during ABC Saturday-morning cartoons. “Three Is a Magic Number” and its PSA-esque descendants like Muzzy or Téléfrançais! taught kids math, grammar, history, and science while also serving as an antidote to the increasing barrage of commercials being pitched directly to wide-eyed, sugared-cereal-hungry audiences.

Many generations have been exposed to Schoolhouse Rock! since its debut, thanks to the shorts themselves, viewable on Disney+, as well as the many homages and parodies that wound their way through pop culture. But
Gen-Xers were basically homeschooled on “Three Is a Magic Number” and the shorts that followed, to the point where it seems fair to argue that the children of the 1970s became MTV’s earliest music-video-obsessive adopters, in part because Schoolhouse Rock! trained them for the moment.

https://www.vulture.com/article/most-influential-best-scenes-animation-history.html