For a long time I was thinking about what to do with the tilt sensor of the Boost-Set. A mechanical scale seems to be a decent application to teach simple mechanics and the center of gravity.
Furthermore, this model contains some learnings about measurement and control systems. To efficiently reach equilibrium the MOVE-Hub starts with larger movements which it refines after each passing over the point of equilibrium. 
All parts are contained in the Lego Boost Set 17101.
The download on rebrickable.com includes the Lego style building instructions, instructions on how to code the program and how to calibrate the system.
There is still some room to improve the program and experiment on your own.