I know this episode aired in 2004, but I was just watching it again today and it made me laugh just as hard as I did last time. And this time I remembered to write down the dialogue:

Lisa: I have to research a paper. Where did all the books go?
Librarian: Books? Books are for squares! We’re now a multimedia learning center for children of all ages… but mostly bums. (motions to a table full of bums — and Homer — sleeping).
Bart: Aye, Carumba!
Lisa: (looking at the few materials left) “Everybody Poops: The Video”??? “Yu-Gi-Oh! Price Guides”???

As Nelson would say, “HA! HA!” ;)

Of course the librarian was a matronly older woman who fit the negative stereotype, but I won’t touch that one…