I've got nine hens. On three different occasions I've picked up more than nine eggs. I'm always checking for eggs so I know I didn't forget one from the day before, much less three times. So....1) either the guys are messing with me and putting eggs out (don't think so, they aren't the prankster type) or 2) someone is laying more than one a day or 3) my rooster is laying. What the heck?
More eggs than hens.
It has happened before - there's another thread on here about that very topic: http://www.backyardchickens.com/t/285795/can-a-chicken-lay-more-than-one-egg-a-day. It's rare that a hen will lay more than one egg in a day, but it does happen on occasion.