What are some art related hobbies for 6th grade girls?

Origami, because its easy, you only need a piece of paper to do it, it doesn't make much mess, and there is such a big range of things you can make by just folding a piece of paper!

There are lots of Arts and Crafts a girl can do at home, as long as she has the supplies! Kits can be bought at a store and ideas may be found online. Use stickers, paper, markers, etc. to make greeting cards to send to family and friends. Learn to knit or crochet or sew.