My little sister thought it would be fun to make a volcano with diet coke and mentos. We had done this experiment before, so we brought the supplies into the driveway and set it up as close to the sidewalk as we could get. Just as we put the mentos in and ran away, my elderly next-door neighbor and his dog started walking closer and closer. We yelled for him to move out of the way, but since he's old and can't hear, he and the dog walked right in front of our volcano! I don't think that dog (or his owner) were prepared for a coke bath! Oops!