The illustrated equipment goes on a level track. The black cylinder is spun up by a pull string and then the fan is used to blow air at the cylinder (perpendicular to the track). The resulting motion of the cylinder cart is based on the direction of rotation and the direction of the air flow.
NOT PICTURED: A baseball sized styrofoam ball is thrown across the room with as much backspin as you can muster. The ball will curve upwards. You can also make the ball curve sideways, but this is harder for the class to see.
Both demos depend on the fact that a surface moving towards the airflow will have a higher pressure (lower velocity) than the surface moving with the airflow.
References: Hetch Chpt. 11, Fig. Q17
This demo can be found in cabinet A on shelf 4 of the UCSD PUL Demo Room
(WLH 2015).