Mark-Paul Gosselaar was cast as Zack Morris at just fourteen years old after casting director Shana Landsburg was struck by his charisma and good looks during a quick read-through.

Dustin Diamond was cast as Screech because Gosselaar himself insisted Diamond was perfect for the part, believing Diamond was essentially Screech in real life; producer Peter Engel later realized he had misread Diamond's head shot and that the actor was considerably younger than the rest of the cast.

Lisa Turtle was originally written as a rich Jewish princess from Long Island, but the character was rewritten after Lark Voorhies auditioned and Engel decided she was perfect for the role.

A.C. Slater was originally conceived as an Italian-American, John Travolta-type army brat, but after casting proved unsuccessful the role was opened to other ethnicities, leading to Mario Lopez, a dancer and drummer from Kids Incorporated, winning the part two days later.

For the role of Kelly Kapowski, producers narrowed the choice to three actresses -- Tiffani-Amber Thiessen, Elizabeth Berkley, and Jennie Garth -- before Engel convinced the others to cast Thiessen.

Elizabeth Berkley had originally auditioned for a different role on Good Morning, Miss Bliss but lost it because she was too tall for Gosselaar at the time; she was later cast as Jessie Spano after producers struggled to fill that role.

The principal character Mr. Belding was originally an older, humorless man named Gerald Belding played by Oliver Clark in the 1987 Good Morning, Miss Bliss pilot, before being rewritten as younger and recast with Dennis Haskins for the retooled series.

Saved by the Bell was a retooling of the prime-time pilot Good Morning, Miss Bliss, which starred Hayley Mills as a teacher and had failed to find an audience even after being picked up by the Disney Channel.

NBC president Brandon Tartikoff wanted to drop the Miss Bliss character entirely and focus on the teen characters, aiming to create a live-action Saturday morning comedy since NBC was losing its 10-to-12-year-old animated audience.

Producer Peter Engel was initially skeptical about making children's programming, but his wife convinced him to take on the show, after which he relocated the setting from Indianapolis to a fictionalized Los Angeles neighborhood called 'the Palisades.'

Senior producer Tom Tenowich suggested the title 'Saved by the Bell' in a meeting; although Engel hated the name, Tartikoff loved it and it stuck.

Composer Scott Gayle wrote the show's theme song in direct violation of Engel's explicit instructions not to reference the title phrase 'Saved by the Bell,' yet Engel ended up preferring Gayle's song over four others that had followed his rules.

Due to budget constraints, most of Saved by the Bell: Hawaiian Style was actually filmed in Santa Monica, with only shots that could not be faked filmed on location in Hawaii; real-life lifeguards were hired as extras to ensure cast safety during beach scenes.

Dustin Diamond published a tell-all book in 2009 called Behind the Bell, which painted an unflattering portrait of his former castmates and included a claim of having slept with 2,000 women, including an NBC vice president 18 years his senior; he later blamed his ghostwriter for fabricating parts of the book.

For a 2009 People magazine reunion photo shoot, Dustin Diamond was not invited due to poor relationships with the rest of the cast, and his image was digitally edited out of a reused 1989 cast photo for the magazine's cover.

An unauthorized stage parody called Bayside! The Musical! debuted in New York and was named a New York Times Critics' Pick, featuring appearances from original cast members Dustin Diamond and Dennis Haskins despite containing strong language and adult content in contrast to the original show's wholesome tone.