The wind car from the blue LEGO Education set surprisingly goes toward
The project is built in two parts from instructions A and B.
Which side the crown gear goes on is important.
When the car is set facing away from the fan it moves to a point of
of the force from the air and the friction of the slipping wheels
against the floor.
Different wheels give a different equilibrium point.
Try making the car from other sets and different sails.