Robotics for Grandparents, Day 3

On Monday, I introduced the class to some new blocks: Loop, Switch, and Random, and to the idea of data wires to connect blocks.  The problem was to build a bumper car that would stop, back up, and turn when it encounters an obstacle.  Their first strategy was to move forward until it touched an obstacle, then stop, back up, turn left, then move forward again.  The second strategy was to use the Random block to decide whether the turn should be left or right.