Answer:
Teenage girls are pros at creating me. Learn me in classes.
You use me between your head and your toes the more I work the thinner I grow.
People see through me, but none pass through without killing me. I can be anywhere, and can be seen double or single. What am I?
I work when I play and play when I work. What am I?
My tail is long, my coat is brown. I like the country, I like the town. I can live in a house or live in a shed, and I come out to play when you are in bed. What am I?
I am your mother's brother's only brother in law. Who am I?