A Phys. Ed. Balancing Act:
We saw this done with a taut cable tied between two trees about a half
meter off the ground: students line up on both sides of the cable, then
hold their hands up to help a classmate walk the length of cable without
falling off. At school you might use heavy rope, or just a board on edge.
If that's too easy, have the walker hold their hands on top of their head.
