Saved by the Bell: The College Years - Season 1 Episode 6 -

It's homecoming weekend. Leslie's parents come to visit her. She is sick of their controlling ways, so she asks Screech to be her date in order to freak them out a bit. Screech agrees to be especially geeky for this event. He does a good job of freaking them out, but eventually they figure it out and they agree to back off and allow Leslie to make some of her own decisions from now on.