A leader points to the noses of three people in the group. Say, “There’s a triangle that goes from John’s nose, to Matt’s nose, to Mary’s nose. Who’s triangle is it?”. Of course, the answer is deceptively simple--the triangle simply belongs to whoever speaks first.
Gather together a number of random objects (sticks, marbles, really anything will work here, as long as it isn’t too big). Use the objects to create some sort of pattern on the table. Very subtly, place a number of fingers on the table as well. Tell the group that the pattern symbolizes a certain number, and have the group guess various numbers. The correct number is the number of fingers you have on the table. Keep changing the pattern until the group figures out that the number has nothing to do with the objects.
The RIGHT Party
Have your group sit in a circle. Tell them, "I’m hosting a party. It's not just any party, it's the RIGHT party. And everyone wants to come to the RIGHT party. But to come to the RIGHT party, you have to wear the RIGHT clothes." Then describe an article of clothing that you’ll wear to the party. Go around the circle and have everyone ask if they can wear certain things to the RIGHT party. In order to come to the RIGHT party, you need to wear the clothes of the person sitting on your right! If they describe any other articles of clothing, tell them that they can’t come.