Agkistrodon contortrix. A student noticed him draped across a manhole cover at the edge of the back drive - only a few yards from the back door of the fifth grade hall. We backed into a safe semi-circle on the drive. We watched the snake - frozen (a defense mechanism) except for the frequently flitting tongue. I sent two students back to the room for the camera. And I used this unexpected teachable moment to present an impromptu lesson on safe conduct in the woods, respect for nature, food chains, camouflage, defense mechanisms, pit vipers, "venomous" vs "poisonous", etc. . The children exhibited an unusual degree of attention. Ahh, the benefits of using the environment as a context for learning!
In nine years of roaming our wild campus this is the first venomous snake I have encountered. Copperheads are pretty common in these parts, so I was not surprised to see him. Still, an exciting morning.