The tree outside our house is "shedding" it's bark, and our front yard is covered in the stuff. Mostly we've just been stepping on it for that satifying crunch sound, but yesterday we gathered some up and brought it in the house. Newspaper spread on the table, we got the markers and tried writing on the rough tree bark. However, it was gritty enough to make it difficult to write.
So next...chalk! Brought out the chalk and the color came out bright and wrote easily. We only had white available to us (meaning, I was too lazy to go in the shed to find the colored ones). I told Kay how paper is made from trees, and how a long time ago people used to use tree bark to write on. When we were finished, we threw our bark art outside and as it fell to the ground heard - yes - that satisfying snap as it broke into pieces.