If your little artist got a bit creative on your walls instead of paper, there are several methods to try to remove the crayon before resorting to repainting your walls and grounding the child for life.
Please note that these methods are intended for painted walls, not wallpapered walls.
Painted walls that have a more glossy sheen will be easier to clean than walls painted with flat paint that could rub off while cleaning.
All of these methods should be tried in an inconspicuous area first to be sure it does not damage your particular wall.
You can use a Magic Eraser cleaning sponge to gently clean the crayon off of your walls, but be careful not to scrub too hard and remove the paint.
Use a pencil eraser to try and erase crayon on your walls, but don't scrub too hard.
You can also try using slightly damp baby wipes to wipe the crayon off the wall.
Use a damp rag and a little baking soda to lightly scrub crayon off your walls.
Toothpaste (Not Gel)
You can use traditional non-gel toothpaste in order to remove crayon off your walls.
Rinse with a damp rag afterward to remove all residue.
You can melt the crayon off your walls using a hair dryer, then wipe up the wax with a paper towel.
You may have some WD-40 lubricant in your garage that can be used with a paper towel to remove crayola off your walls.
Here are a few other options for crayon cleaners that might work: mayonnaise, peanut butter, vinegar, all purpose spray cleaner, baby oil, shave cream, hairspray, goo gone, turpentine, lighter fluid, hand lotion, ammonia, powdered dishwasher detergent, non-stick cooking spray (such as Pam), powdered cleaner (such as Bar Keepers Friend), and dusting spray.