Opposite Actions Activity 
This Activity is meant for Cub Scouts.
Two scouts step forward to face off.
The challenger pats his head at the same time he says, "I'm rubbing my tummy."
The other scout must respond by rubbing his tummy and saying, "I'm patting my head."
If the responder gets mixed up, the challenging team gets a point.
Repeat with each team taking turns doing the challenging and responding making up whatever actions they think of.
Play until one team reaches 5 or 10 points.