I just spent an hour scrubbing an eight-foot section of wall in the hallway. Dear PBU (people-before-us), have you ever heard of washing your walls every now and then? No? I didn't think so.
I used to scrub marks off of walls with Mr. Clean's Magic Eraser. It worked so well that it made me wonder exactly what chemicals were in there working away. Some people claim that the eraser is toxic, and others say that's just an urban legend. But in any case, I found that baking soda works just as well for me. I put a little bit on a damp cloth, rub away, and the wall comes clean. Now I store little boxes all over the house, in every bathroom and in the laundry room and kitchen so it's always within reach. Really, if you have the choice, why not clean your house with things that are safe enough to eat? Yes, I feel very 1950s as I write up cleaning tips, but even in the twenty-first century, cleaning is part of life. And oh baking soda, we do love you so.