Trivia: During the final 2 seasons of Saved by the Bell, most notably the season with Tori and the one following it, look for actor Casper Van Dien in the background of some episodes. He appeared in many scenes throughout the final 2 seasons as a random background extra, most notably in the locker hallway scenes. This was before he made it big in Hollywood.
Trivia: The high school hallway used is later used in the Disney series That's So Raven.
Trivia: Of the main six characters, Screech is the only one whose father never made a physical appearance on the show.
Trivia: In the show Tiffani Thiessen was the love interest of Mark Paul Gosselaar as Zach - he actually had a relationship with Lark Voorhies.
Answer: As far as I can tell Jessie and Kelly decided to leave the show because their contracts were up and they wanted to pursue other things. But there were still episodes of Saved by the Bell left to tape so Tori came along to fill that void. Jessie and Kelly were supposedly still at Bayside, but they were "off-screen." The Graduation episode was filmed before Kelly and Jessie left the show.
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