4.  methods/classes. functions. return. parameters

    lab: Make it so that main creates an instance of that robot.
         Create methods which turn the robot right, or left. Which 
         go forward x distance. 

         Have the robot go in a square. Useing different tires.
         Shows how friction and such affects the actual distance 
         travelled, and actually getting it to return to where it
         started is a harder problem that one might first realize.

         Or, if you want, add a sensor, and a SensorListener class.
         Have it backup, or go forward on a specific event. For 
         example the obstacle avoider (call back up and turn on sensor
         activation). 

    projects:
         Use a rotation sensor to see how far the robot has gone
         in a standard distance.
         Use this to try to improve the robot going in a square.

         Make a method to return the battery mV value. 

         Make a method to have the RCX go forward, on the test pad,
         and count the number of green squares.