Wood comes from trees, right? It is full of potential chemical energy that can produce heat when it is put into a stove or fireplace and burned. Yet, in this story, the Earth’s bounty seems to produce a cooler room. What can be the cause? Thermodynamics, the branch of physics that deals with the conversion of various forms of energy from one to another, affecting things such as temperature, is the answer to this riddle, since the flow of heat goes from warmer to cooler objects in a closed system. This story can lead to a discussion of our uses of the words warm and cold in the colloquial sense as compared to the words physicists use.