Executive Toy -- The Kinetic Ball Challenge

This graphic courtesy of DeskToy.com

THE CHALLENGE:
As shown in the pix above, one of the suspended balls has been pulled away from the rest, and has just been released.

What happens?

The executive challenge is to explain what happens to a five year old -- in a way that satisfies the child as well as you.

According to Piaget, a five year old is at the concrete operational reasoning stage .

Piaget and his co-workers never (to this writer's knowledge) used this executive toy in their studies of children's thinking. But a closely related puzzle was used:

Piaget's Colliding Balls Puzzle

A row of red balls is sitting at the botom of an inclined ramp. At the top of the ramp there is another ball. What happens when the released ball comes down the slope, and collides with the nearest ball?

This problem is best posed using real balls - and not as a theoretical exercise.

Five year old's solutions (after actually witnessing the collision)
When the ball came down the slope the slope, it jumped over the other balls and kept on going.

Eleven year old reports (after actually witnessing the collision)
The ball came down, hit the first, which hit the second, and so on. The ball at the free end just went on ahead.

If the eleven year old is then asked, "How would you explain what happened to another child ?"