I started writing fanfic when my daughter was ten. I had heard many times that if you want your kids to value reading, you should let them see you read, so I figured the same thing applied to writing. She started with Harry Potter stories, and she quickly learned to value the mechanics, which she had scoffed at before, after having a story or two rejected for being so sloppy in grammar, spelling, etc. She's twenty now, and she still writes.
