Honestly I have not used them but I would assume if they are water based then it would be easy to come off. My granddaughter used some a few weeks ago and it did come off easily now that I think about it
I am a painter and all you need is some soap and water to clean it up. I do oil paints, water color, acrylic paints, and charcoal pencil rubbings of old grave stones. I fanned you and am watching too.