what in the world?

I came home the other day after a semi-crappy day at work, put all my stuff down, said hello to everyone and turned to go back down the hall and came upon this:

Most of you are probably wondering the same thing I said out loud, "Why is there Play-Doh stuck to the wall?" Rick and JT both feigned ignorance but Zach proudly stepped forward and announced, "Momma, that is not Play-Doh, (note that once again he is using his tone of pure disgust at my ignorance) that is the rock Luke threw against the wall." Not sure what I was thinking.