Get the scouts to experience a disability that they may not realise exists, and even perhaps someone in their own scout troop has
cheap plastic safety glasses, post it notes or insulating tape, non-permanent marker, scissors
Copied from hemianopia.org
HOW HEMIANOPES SEE
1. Choose who gets to be the hemianope and who gets to be the sighted person.
2. The hemianope gets to wear the glasses.
3. The sighted person should hold the marker.
4. Stand facing each other at armâ€™s length (closer if necessary)
5. The hemianope should look straight ahead at the sighted person but into the distance.
6. The sighted person should dot the eyeglass lenses, placing the dot directly in front of the hemianopeâ€™s pupils. The sighted person should recheck the marks by backing away to armâ€™s length and verifying that the dots are directly over the pupils of the hemianope. If necessary, wipe off the dots and remark the lenses. This measurement is critical.
7. The hemianope can now take off the glasses.
8. Either person can apply the post-it notes to the eyeglass lenses. (the edge of the post-it should run through the center of the dot, as shown, above)
9. Secure the post-its to the glasses with scotch tape (not the viewing part of the lenses) onto the post-it then over and under the frame to the back side of the lenses as shown.
10. Snip away the part of the post-it that hits the nose, then put the glasses on.
11. The hemianope should now look straight ahead. Notice that to the right side, almost as much can be seen with the post-its in place as without them. This is because the peripheral vision of the left eye, toward the nose, overlaps the blind field of the right eye, allowing almost total right side vision.
12. The hemianope should now close the right eye but keep the left eye open. Observe that the right side can be seen but to a lesser degree. Some of the peripheral vision that the right eye covered has been lost.
13. The hemianope should now close the left eye leaving the right eye open. Observe that there is no peripheral vision overlap so only objects to the direct right can be seen.
14. The sight person should now stand on the left side of the hemianope and allow the hemianope to take his/her arm for a walk around the room. The hemianope should not peek around the post-it notes and should keep the eyes facing directly to the front. (The pretend hemianope can tilt the head to the left to get a better view. A true hemianope cannot do this.) To keep the simulation as accurate as possible, the hemianope should look directly forward.
see also http://en.wikipedia.org/wiki/Hemianopsia
get half a dozen to be hemianopes and play a ball game or any activity with the others. It's easy when the world around you is calm and predictable, but when people around you are moving in random directions at speed it becomes much more difficult.