Today one of my physics classes did a lab in the gym that involves bowling balls and brooms. Basically, the point is to sweep the balls along with just the bristles of the broom and short sweeps (no pushing), so they can get a sense of inertia and how small applications of force affect movement.
I thought it went well. They had 7 different tasks to complete, including accelerating it from rest, keeping it going at a constant speed around the "jump circle" in the center of the basketball court, and turning a sharp corner. One kid was always recording the group on my iPad so that we could get some good examples of the motion and even run it through my video physics app to see if the speed really was constant.There are 15 kids in the class, and I was pleased by how well they did staying on task and not getting hurt.
Well, turns out there's a lot that a teacher can miss! When I looked at all the videos they'd taken on my iPad, I was shocked! Misbehavior after misbehavior! One kid trying to balance on a bowling ball, playing ninja with the broom, and nearly crashing into our poor exchange student (all the same kid). Another was holding the broom in one hand and a soda in the other (how did I miss that for half an hour??). One was stealing balls, and they were all just constantly harassing one another.
I did learn an important lesson though. If you want to catch teenagers misbehaving, give them a recording device. They'll automatically record all of their worst behavior, and all you have to do is review the evidence and punish accordingly.