Find a tree branch which can be snapped into smaller and smaller pieces. Start by having everyone touch the branch at the same time. Then break the branch in two, toss out half and have everyone touch the branch at the same time again. Continue breaking the branch and throwing out half and doing the same. As the branch gets smaller it will get harder for everyone to touch it. The group will have to work together to align themselves so that everyone can touch it. After 4 or 5 iterations stop for discussion.