Try to hit a frozen player with a ball
A Soft Ball and player
When the ball is loose everyone can run around.
As soon as a player picks up the ball he/she shouts freeze.
All players then stop. (leader to pick out ones that carry on)
The ball carrier then throws the ball at a players legs
If it hits below the waist the player is out. Above the waist the thrower is out.
The player can "Dodge" by jumping or can move sideways but their feet must not move and they cannot squat down.
To make it even more fun you can have it in teams where they can transfer the ball between members of the same team.