The absolute best place for a kid to hide a mess is under the bed. There's quite a bit of area under there, so it has the potential for hiding multiple messes. It also offers easy access to a kid but is a tougher stretch for mom's aching back and tired knees. There's a psychological component to hiding treasures -- and disasters -- under the bed, too. It's in the middle of a kid's personal "territory," so it's a more desirable place to stash the really bad stuff -- you know, the lousy report card, the hopelessly stained pants and that pilfered lawn gnome the neighbor's been looking for. If you've wondered where your good wristwatch disappeared to, or what happened to the crystal candlesticks, check under the bed in your kid's room.
This isn't all bad news. If you decide to keep the extra leaves to the dining room table under your child's bed, there'll be less real estate in which to conceal the carnage. Until then, performing an under-the-bed check every once in a while couldn't hurt. Go prepared though. From moldy pizza crusts to month-old underwear, you never know what you'll find.