What is a good way to teach rest and exercise to kids, (this is for a nursing class).?

This will be at a health fair and i want a way to do it where it will be fun and have some sort of acvtivity, the demographic of kids is mostly the children of international students(80%) and the age that i want to teach to are from 4- 12 years old. I am not totally limited by funds or space, (ill be paying out of my own pocket for anything but have some extra cash). I could do a number of things that would include a game of soccer or whatever it may be, but the trick of this is to tie it in with the more dull nursing aspect of rest and exercise. It also must have some sort of actual factual information with it, that i can come up with. My other classmates will be having booths on other subjects, i would like to have all the kids to be at my booth most of the time.

For rest let them breath in thru their nose and out thru their mouth making blowing sounds.

For exercise you could have jump ropes. They can jump individually, or have two people hold ropes. They can jump fast, slow, run in, or other ways. I have found that boys and girls both like jump roping. It doesn't require much planning or space.

If you want something less active you could set up a bean bag throw. Use hula hoops spaced out for them to throw at. Give small prizes for the ones with the most points.

After they exercise take their pulse, let them put their hand on their heart and feel their heart beat, then again after they rest.

Play soft music and ask them to roll like the waves of the ocean.