I once helped a student do an experiment with the center of mass motion of a dancer as she did some ballet moves (leaping, whatever they call that.) Figuring out the location of the CM of a human body isn't the easiest thing to do, so this one's a challenge.
Golf is good, you can also do air resistance using a tennis ball cannon, or that thingy they use in baseball to fire the baseballs at the batter.
That's all I can get off the top of my head. I'll try to think of more.