Students create a free hanging mobile to illustrate rotational equilibrium. A project log is used to keep track of progress, data, calculations, modifications, and reflections. The finished mobile is illustrated on a blueprint along with the specifications of the mobile (lengths, weights, and torques). During 2-3 in class work days I have scales and meter sticks available for students to use to make measurements and have students provide the needed materials. Completed mobiles can be hung aro