This is my favourite activity to do in science with all of my students.  Both of my science classes have begun creating a well structured Rube Goldberg mechanism including five structural components, an internal and external force.  So far students are in the planning phase and working on their prototypes.  I am so pumped to see what they will come up with! Here is a peak at one group that is working on their prototype. Awesome job guys! (and yes that is a robot arm)