Be VERY, VERY careful when using blue chalk! It has been known to not come off. Always pre-test your fabric when using chalk. I just took a custom quilting class and the instructor swears by using school chalk and a chalk sharpener. She said the cheaper the better. I'm going to buy some. Now, if you are using stencils, I highly recommend the Pounce Pad & loose chalk refill. Very easy to apply. You can get white, blue, and grey chalk. I use white for dark fabrics and grey for light fabrics and I steer clear from the blue. I guess you'd say I have Blue Chalk Phobia because I've seen what it can do. Nita