The ball on top of the ramp has potential energy and when it is pushed onto the incline, the energy changes to kenetic energy.  At the end of the ramp is another ball that is in contact with the ball coming down the ramp.  The energy trnsfers to the second ball causing it to move onto a little lever that is attached to a string connected to a floor board on the platform.  The string is pulled down by the weight of the ball which opens the platform ramp to come down.  A third ball with potential energy rolls down the swirling ramp changing to kenetic energy.  At the end of the ramp is a lightbulb tape to a battery with a paperclip.  The paperclip is opened up so that it has one end on each side of the battery.  The top side of the battery isn't touching the battery to light up the lightbulb until the ball on the top of the ramp hits it.  A block is tied to the middle of the battery so it doesn't fall over.