Think before you act
Credit Unknown
 

Things you'll need:

1.      A brown paper lunch sack
2.      Several individually wrapped pieces of candy
3.      One egg (raw)
4.      A towel or blanket to place under the bowl and another towel to clean the individuals
         up (or baby wipes work well for cleaning off sticky things)
5.      A large bowl
6.      A small stool (optional)

Setting up the game:

In a brown paper lunch sack place several individually wrapped pieces of candy and one egg (raw).  Lay a towel on the floor and put a large bowl on the towel.  Put the stool next to bowl (if you are using a stool) stand on it or stand up next to the bowl holding the bag of treats.

Rules:

1.      Those playing the game are to sit on the floor around the bowl and not to look up.  If they look up they have to leave the game. 
2.      People not sitting on the floor around the bowl are not allowed to say anything or make any noises. 

The Game:

Tell those people sitting around the bowl you are about to drop things into the bowl.  If they want them, they have to grab the items before the other people. 

With the bag high above your head, drop one piece of candy in the bowl.  Usually they will pause and think before they grab.  Keep dropping candy into the bowl faster and several at a time until the kids are not paying any attention and are frantically grabbing at the candy before it even hits the bowl. (remember if they look up they have to sit on the side lines.)  Then when they are so involved in the grabbing, drop the egg.

It's pretty messy, but all those who were rushing into the bowl, are now covered in egg. 

The Moral of the Story

Then you relate to them that temptation makes you think you are about to get something great.  Sometimes you feel like what you're doing is okay, or great, or was worth the risk.  But eventually, the temptation will lead to a place or thing that you didn't really want.  Or something will happen that you never wanted to happen.  Satan entices us with the good parts of the sin until we're so involved that we don't realize we're about to be covered with the bad effects of sin.  Satan wants us to stay messy. 

Then you can hand them the towel (or baby wipe), who represents our Savior.  (Any time I talk about sin and mistakes, I always want them to know what to do if they make a mistake, sometimes they don't understand that part.)  "Sometimes we do get caught up in the temptations.  When we do make a mistake never forget that our Savior wants us to immediately go to him and ask for his forgiveness and for his help to make ourselves whole and clean again.  He loves us and wants us to come to him.  Never forget what he has done for you!"