Tall Tales, Lying, or One-Upmanship?

I wrote a few weeks ago about a child (I'll call her Meredith) in one of my reading groups who told me a story about how when she tried to pull something out of the ground, it flipped her up into the air. And her brother tried it, and it flipped him into the air, too. And then the very same thing happened to her father - flying in circles in the air! This week I told the children about riding in the airplane with PawPaw last weekend. Meredith immediately piped up with the story about the time her father was flying a helicopter and shot her brother from the air. (I guess this happened after the air flipping experience.) Methinks Meredith has a need to have a bigger and better story. Classic one-upmanship. Today I asked her if she had someone at home to read her book to, and she replied that she had a sister in the first grade. A pause. "No, wait," she said, "She's not in the first grade, she's in the 'twenty-grade.'" The other kids just looked at her.