But his career didn't take off until he stumbled into kids music.
In the mid-'90s, Covert decided to take a break from touring and start teaching, partly to hang out with his young daughter who was in a "Mom and Tot" class.
A parent in his class, who owned a record label, asked Covert if he wanted to do a kids record. He did, but wanted the music to be enjoyable for adults too.
In 2000, he started the band Ralph's World, and by 2001, his first album, named after the group, was released. It was a hit.
Eight more albums followed, one of which was the 2006 Grammy-nominated Green Gorilla, Monster & Me.
Ralph's World has sold more than 300,000 albums, more than three times what The Bad Examples sold.
Covert credits his success mostly to good timing: "I happened to accidentally be a first surfer on the wave."
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