I've not used chalk but have saved these hints when and if I decide to; haven't tried the tips so I can't vouch for these methods.
Spray your chalk lines ...
When using chalk rollers to mark your stencil designs, spritz over the chalk lines with hairspray to keep it from rubbing off while you handle the quilt. The marks disappear in the laundry with no problem.
~*~*~*~*
I keep old nylon knee highs near by. They are excellent for removing chalk markings. They are also good for removing deodorant mishaps on your clothing. -
~*~*~*~*
in response to blue chalk used to mark a quilt:
I massaged detergent over every traced line, rewashed on gentle and dried on no and then very low heat. (My washer does not have the type of agitator that is too rough, so I lucked out).
HTH