A pinball machine is built using two kinds of simple machines: a lever and an inclined plane. The lever shoots the marble to the top of the box with lots of force. The inclined planes make the marble wind its way down to the bottom. Do you notice how much testing it takes to get your pinball machine to work the way you wanted it to? Testing and experimenting are a big part of being a scientist and engineer - that's how brilliant solutions and great discoveries happen! Make a pinball machine that can shoot a marble and send it zigzagging down an obstacle course.