I might be wrong, but I'm fairly sure Lois's high school experiences were mentioned in The Prankster, for one episode. I have the idea that they also mentioned the name of the school in that one, but don't quote me.
The episode with the reunion you're thinking of is It's A Small World and there are definitely references in that one. If only I could remember what they were, I'd be much more help to you. <G>
I can send you the scripts to both of these if you like, if that would help?
LabRat