Well, this was interesting.
For the qualitative testing experiment I made a pretty simple pendulum testing model. I have 3 pendulums with bobs of different masses but the same length, and then two pendulums with bobs of the same mass but different length. This is meant to qualitatively test the hypothesis that the period of a pendulum is proportional to the length of the string/wire/linear-non-stretchable-object. If this hypothesis is true, then the 3 pendulums should oscillate together without collisions. This is true for small amplitudes, but for larger ones the relation clearly does not hold. File can be found here.
For the quantitative experiment, I again went with something oscillatory, this time with a mass/spring cart system. Students can measure the position vs time, and from that graph ascertain the period of the oscillation. By pausing and adding or taking away mass, students can determine how exactly period of a spring is dependent on the mass and spring constant. File can be found here.
For fun, I made something called Beware The Rainbow. All of us are well aware that Lord Unicorn Pegasus, enemy of the Robotic Republic, is a vicious creature that demands sacrifice once every thousand years as tribute for protecting our universe from invasion of synthetic life. Seeing as the last sacrificial ceremony in honor our lord and savior was 500 years ago, I created a short simulation…for posterity. Simulation of our future can be found here.