This is the classic Fun Magic Coloring Book. It is getting hard to find this specific classic version. I used this trick (not this copy) in hundreds of shows and it always gets a good response.

You show a coloring book to the spectators. A child comes up to help out and with a wave of the hand or wand, all of the pictures become colored in! After calling for a round of applause for the child, you explain that this is a trick you use a lot and before the child goes back to their seat, they will have to erase what they've done at put it back to the way it was at the start of the trick. Have the child wave his or her hand over the book while saying "Poof!." The child does so and you ask, "Did you erase all of it?" "Yes," the child says. But when you show the inside, all the pages are blank! No color and no lines! "When I said erase all of it, I didn't mean the lines too! You'll have to undo what you just did." You have the child wave his or her  hand again and say "Foop," which is "Poof" backwards. The child does so and now the book has returned to the way it was at the start of the trick.  

Comes with written directions. 

Note this is more expensive at Amazon.