Biology teacher leaves a full class of 15 year olds around her desk, which has a pair of very large cows lungs with the windpipe still attached. Boy A grabs the windpipe and inflates them by mouth, then points it into the face of boy B and removes his thumb from the pipe. Stinking fetid cow lung smell causes boy B to instantly go green then turn and throw up into the shocked open mouth of boy C, prompting multiple pupils to throw up everywhere. The teacher was out of the room for less than 30 seconds and all Hell had broken loose.