Season 2: Episode 17: The Prom
Zack and Kelly plan to go to the prom together, but then her dad loses his job and she decides that she shouldn't spend any money on the prom; Screech asks Lisa to the movies; Slater and Jessie decide to go to the prom together. Zack arranges a special prom just for himself and Kelly. Kelly and Zack share the first kiss, while Jessie and Slater have their first date.