temp building - When I was in school, we knew those as bungalows, and they were permanent fixtures.
There's still no name for the boy who kisses Sally before Butters does.
Butters has been kissed a few times, but he hasn't kissed back or kissed a girl himself until this episode. He did kiss Cartman, but Cartman isn't a girl. :D
Scott Malkinson returns, so he may be a regular character on the show now, and thus, a new classmate in fourth grade. He seems to have a bad home life, as he found Sally's kiss quite comforting.
Sally's pretty generous - she gives Butters 40% of her take, so it's 60-40, as Butters explains later on.
Ashley looks and dresses like Anne Polk.
The Player's Ball has been a Chicago tradition since 1974, when it was first held as a birthday party for Don Juan, now known as Bishop Don Magic Juan. He is represented here by the pimp Butters talks to - the pimp's belt buckle reads "BISHOP."
There are 3D effects everywhere. Two of the pimps around Butters at the convention have realistic shoes on.
The goblet the pimp talking to Butters is drinking from can be found in novelty stores, with the word PIMP glued onto it.
The Groundskeeper from "Damien" back in season 1 returns, with new clothes on.
The song playing when Det. Yates pops out of Kevin's birthday cake: Peaches - Fuck the Pain Away. Before that it was Sam the Sham and the Pharaohs' "Wooly Bully."
Butters' work sheet has a listing for Yolanda, but Yates, calling himself Yolanda, doesn't come in and ask about the company for several minutes, so Yolanda shouldn't have been listed there.