A raw egg, food coloring, hypodermic needle (see your local pharmacy), a clear bowl.
Color the inside of the egg by injecting it with the needle full of food coloring.
Show the egg. Put it into the clear bowl. Ask your family to tell you everything they know about an egg. Describe an egg. What is the egg's potential? What are its uses? What would you expect to find inside an egg? How do you know all this about an egg? Crack open the egg into the bowl and watch your family's reaction.
What changed the egg's contents? We are born as special children of God. Why do we sometimes fall short of our potential? What do we sometimes let enter into our lives that keeps us from reaching our potential?
"All the water in all the world, no matter how hard it tried, could never sink the smallest ship, unless it got inside. And all the evil in all the world, the blackest kind of sin, could never hurt you the least little bit unless you let it in." (Author unknown)