<p>The Command strips do not mess up the walls. You can even use them on drywall and they don't mark up the walls. I had 10 picture frames hanging in my room on the drywall with them and i recently took them all down - hooks and all, and not one mark anywhere. They are great.</p>
<p>The sticky tack never stained my walls at school, it stained my posters... however blue sticky tack stained my sisters wall at home, but that's drywall and purple paint.</p>