The paragraph that would most effectively establish the narrator's point of view is:
3. I am trying hard to sound like an expert. Yet, I feel like a fraud. The sum total of my knowledge about origami came from a book I bought at a neighbor's garage sale.
This paragraph reveals the narrator's personal feelings of insecurity and inadequacy regarding their knowledge of origami, contrasting with the authoritative role they are trying to assume in front of the kids. It provides insight into the narrator's internal struggle, establishing a more personal perspective.