Covered in cheese

I emerged from the schoolroom with my oldest yesterday to discover that the two middle sons had covered my basement steps in shredded cheese, like some sort of giant wooden entree. They cleaned it up as best they could, but there's still cheese everywhere.

The funny thing is, I didn't stop to ask them what they were doing or why. It was just, "Who put cheese all over the steps? Well, clean it up." I guess at some point I just ceased to be surprised by anything they do.