1. Here's the only screwed up line I know of (that made it into an episode):

at the end of the episode where the gang pulls an elaborate, haunted suite prank on Zack, here's the lines at the end of the episode:

Z: Did you really leave your blankee here, or is thsi just another stupid prank?

C: Listen (he pronounces it Lis-10), I don't kid when it comes to blankee.

2. There are nods to other kid sitcoms in the lines of a couple of episodes:

In the episode where Zack fakes having dyslexia, and Moseby has a bad cold,
Moseby directs people to their parties: Mrs. Cleaver (reference to "Leave it to Beaver") and Mr. Cunningham and Richie (reference to "Happy Days").

In the episode (I think) where Zack isn't graduating, there is a reference to a kid named Lippincottleman (reference to "Silver Spoons").