If you really want students to wrap their mind around the concept of what falling objects do and aren't "clinging" to the insistence of obtaining the absolute precision of 9.81 m/s2 in lab, then the g Ball is exactly what you're looking for. A favorite experiment with the g Ball is to show students that g is the same for any dropped height. Drop the g Ball from 3 meters, 2 meters, 1 meter, and from 50cm in height... and using d=1/2 at 2 with the measured time, will result in a ~10m/s2 every time! The ball has a timer that is started manually with a push of a button at the instant it is released or thrown. When the ball strikes a surface, the timing stops and the time of flight is recorded. The cool thing about using the g Ball is that it can be used anywhere; outdoors to measure the height of the flagpole, the speed of a student pitch in the hallway, in the conventional lab setting, without the need for computers, expensive data collectors or complicated devices.

Maximum drop height is 12 metres depending on landing surface. Avoid direct impact with the display; drop with display facing up.