There was a short film dealing with creativity where the sesame street characters sit at the table and talk about doing creative stuff. At the end they start killing each other. One of them says "Let us do something creative" again and again.
Did you mean Don't Hug Me I'm Scared? A spoof about educational puppets where they sit around the table and sing about creativity, then go nuts, do gross things and write 'death' (they don't really kill one another, though).