Musician Bob Dorough, 94, best known as a composer and performer for ABC’s educational series of short cartoons “Schoolhouse Rock!,” died of natural causes at his Mount Bethel, Northampton County, home on Monday, his son, Chris, said. Originally a jazz musician, he “set the multiplication tables to music” as musical director for the educational cartoon series between 1973 and 1985, according to his biography.

The cartoons, which returned to the airwaves from 1993 to 1999, focused on teaching children school subjects like history, math, and grammar through songs set to animation. It began in 1971, when Dorough was approached by an advertising executive to put multiplication tables to music, leading to “Three Is a Magic Number,” as well as a “Multiplication Rock” collection.

By 1973, the project evolved into the now-beloved “Schoolhouse Rock!” Some of Dorough’s most memorable songs from the series include “Conjunction Junction,” “The Shot Heard ‘Round the World,” and “I’m Just a Bill.” According to the Morning Call, Dorough still performed some of his Schoolhouse Rock! songs in live shows as recently as 2016.

An Arkansas native raised in Texas, Dorough first began playing music in his high school band.