I once tried to explain football to a guy from Jordan (middle east) and we got stuck on why 50 is in the middle of the field and the numbers go down (40,30,etc) in both directions. That confused the heck out of him. I thought that would be quick and easy and I would then explain what 4 downs meant but he glazed over and gave up about the 50 yard line being in the middle of the field. Oh well I tried.