Answer:
I can be thin but not fat; in your body but never on your placemat. I'm always better when I'm fresh but you'll never see me in the flesh.
You write on me and secrets I can keep. In places never seen. I spin like a top. Though stiff as a board I'm often described like a mop.
I cannot be bought, cannot be sold, even if I'm sometimes made of gold. What am I?
I am a tale in childrens' minds. Though an illusion, I occur every night. I give them a fantasy, I give them a fright. What am I?
What goes up a chimney down but can't go down a chimney up?
I touch the Earth, I touch the sky, but if I touch you, you’ll likely die. What am I?