Magic Marker in a Clothes Dryer?
That new Magic Eraser by Mr. Clean will get it right out. Hope this works
Blood Stains on Sheets?
Soak it in salt water, I would use enough cold water to cover the sheet and then pour in a cup of salt, mix it up and let it sit for a few hours or wet the spot and put salt on it, then let it set, and throw it in the wash.
Dirty Looking Elbows?
My aunt is a quadrapalegic, and the nurse uses one of those pumice stones to scrape away the brown spots, use very gently, and then puts moisturising lotion on it every day. On the days when its not too bad, she has even used a soft emery board. Hope this helps...