Plot hole: Lisa, Zack & Screech all talk to JB as if they have known her since she was little. However, they have only known Slater for approximately four years, so them knowing her from a little girl, as implied, wouldn't be possible.
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Suggested correction: JB is only featured in one episode. The fact the kids knew her already (even if up to four years) doesn't mean she was known since a little girl...just that they all previously met her at some point.
