This happened to me using the blue in the "Dritz Quilting Chalk Cartridge Set" at Joanns! I washed the quilt and the blue remained (this happened to me more than once, you would think I would learn my lesson!) I used the Shout stick stain remover and washed it again... and again (but not drying it, because I didn't want to set in the chalk). Finally, I got detergent and a toothbrush and rubbed it into all the blue chalk spots and it pretty much finally got rid of them all.