I don't know of any home made remedies but I know what you are talking about. I have one of those easels with chalkboard on one side and dry erase on the other. I have cleaner for the dry erase board and it cleans up the dry erase markers from the chalkboard very nicely. Office Max or some other place like Walmart should have it. It's specifically for dry erase boards...it's a cleaner that comes in a spray bottle. A little bit on a paper towel will remove that marker from the chalkboard.