Elmo and octopus are getting off the schoolbus and walking on the "sighwalk" (the wide black border surrounding the glass of the coffeetable). I'd never heard him say sidewalk before.
He also tells knock-knock jokes. Here's a great one he told me yesterday:
Daddy: "Who's there?"
That's as far as his joke goes, but I'm sure he'll remember the punchline sometime soon.