Dad Weir won't allow Lindsay to attend the Who concert because of their "pornographic" song. Mom Weir suggests that she and Dad chaperone Lindsay at the concert. Did I mention how cute Mom is? She's pretty gullible, too, since she actually believes the story Lindsay concocts about sharing the Weirs' concerns about the concert but wanting to keep an eye on Millie. I don't know how anyone could believe a story like that, but maybe it's the simple fact that Millie is allowed to attend the concert that causes Dad to change his mind. He does warn Lindsay, however, "You just keep those boys away from your accordion."
In the car on the way to Go-Cart City, Biff tries to interest the boys in a conversation about basketball. Neal and Sam look mightily perplexed by it all; Bill, of course, is sulking. Biff finally realizes that basketball just isn't going to be a winner, conversation-wise, so he hands Bill a gift: it's fake dog shit from a joke shop. You would expect Bill to be as excited about this as Sam and Neal obviously are, but all he says is, "Oh great, just what I always wanted: doody." The fake vomit and trick dollar bill go over pretty well with Sam and Neal, though.
Speaking of jokes, Nick is performing his song, "Lady L," for Ken. It has got to be a joke. Even Nick couldn't make up lyrics as corny as this:
I said, Lady L, let your soul be free
You closed your eyes and you wouldn't see
The only one who could ease your pain was me.