for me it has to be when Zach says to one his girlfriends "We'll discuss my fee later."

Zach!! You bad boy!!!

Screech- "Jessie, you look good in a towel, now drop it!"

The first time I heard I was like, "WTF?!"

I think an episode where they pair off as couples for a school assignment and Kelly says she wants children and Zack says "maybe one day I can help you with that".

the episode where they're practicing for the class trip with Rod Belding. Jessie was talking about Slater being just great and then Slater said "That's not what you said saturday night" and the audience just screamed.

"That's not what you said saturday night" and the audience just screamed.

LOL... I remember that line!... I wonder what they did that Saturday night. ;)