This lesson is for grades K-3

The teacher picks out one student who will be the moon monster.  The
teacher keeps this a secret so that the other students do not know who
the moon monster is.  The teacher says "The mooon monster is a girl",
then the class raises his and her hands waiting to be called on to guess
someone's name.  If the student gets it wrong, the teacher adds to the
description.  "The moon monster is wearing a red shirt"  The student
guesses again until he gets it right.  When the student gets it right,
the teacher says, "The Moon Monster IS Melissa!"  Then Melissa trys to
tag everybody in the class.  When the other students get tagged they
freeze.  Then the teacher calles everyone back to the center circle
except Melissa who stands over to the side.  The teacher then picks a new
Moon Monster in the same manner except this time Melissa also helps tag
everyone.  You go through this process until you have about five Moon
Monsters.

The little children love this game.  Always stress safety when tagging.