Good Morning, Miss Bliss was originally created as primetime TV sitcom for NBC, with Hayley Mills playing Indiana elementary school teacher Miss Carrie Bliss. However, after the pilot aired, NBC decided they didn't want the show.
Good Morning, Miss Bliss was then ordered by the Disney Channel (with NBC still producing it). While Hayley Mills stayed on as Miss Bliss, the show was slightly reworked with it now taking place in a junior high and new characters being cast (Mark-Paul Gosselaar as Zack Morris; Dustin Diamond as Screech Powers; Lark Voorhies as Lisa Turtle; and Dennis Haskins as Mr. Richard Belding). The show didn't do great in the ratings at the Disney Channel, so it was canceled after 13 episodes.
After its cancellation, NBC decided it wanted to show 'cause it would be great for its Saturday morning lineup. The shows producers then reworked it for its new network and time slot by changing the location to California, setting it in a high school, and focusing it on the students. It also brought the characters of Zack, Screech, Lisa, and Mr. Belding over too and no one ever spoke of Miss Bliss again.