We had about six beach balls blown up for the kids to play with while they waited for everyone to show up. 

We divided the kids up into groups (Tribes of Israel We used six of the twelve.) by tying headbands made of 6 different colors of fabric with the name of their "tribe" written on it.  This made them very easy to keep together. 
We had them rotate through each activity with their group.  When they first get to each activity the instructor gives a BRIEF story or explanation about the scripture that coordinates with that activity. 
We spent about 7 minutes per activity total so there is not a lot of time for long lessons!

1. Sunscreen application
   "Yet you should have been  faithful: and he would have extended his arm and supported you against all the Fiery Darts of the adversary."  D&C 3:8
2. Nephi Builds a Ship 
   "And it came to pass that I, Nephi, said unto my father: I will go and do the things which the Lord hath commanded." 1 Nephi 3:7
   Build folded paper sailboats and race them in wading pool by blowing on them with straws.
3. David and Goliath
   "Thou comest to me with a sword and with a shield: but I come to thee in the name of the Lord of hosts."  1 Samuel 17:45
   Throwing wet sponges at target (We used a real person)
4. Squirt guns
   " The light of the righteous rejoiceth: but the lamp of the wicked shall be put out."  Proverbs 13:9
   Two people race to put out lit candles by squirting flames with squirt guns.
5. Cupcake Walk
   "And when he putteth forth his own sheep, he goeth before them, and the sheep follow him: for they know his voice."  John 10:4
   "Same idea as musical chairs , but each chair has a number.  After music stops all people sit on a chair and a number is drawn.  The child sitting in the Chair with that number gets a cupcake and a bottle of water.  Take their chair out and continue playing until everyone gets a cupcake.
6. Living water
   But whosoever drinketh of the water that I shall give him shall never thirst; But the water that I shall give him shall be in him a well of water springing up into everlasting life."  John 4:14
   Ice cold bottled water to drink with cupcake.
7. Slip and Slide
   "Strait is the gate and narrow is the way, which leadeth to eternal life, and few their be that find it."  Mathew 7:14
   Children take turns on the "Slip and Slide"
8. Tree of Life
   "The tree of life, whose fruit is most precious and most desirable above all other fruits; yea, and it is the greatest of all the gifts of God."  1 Nephi 15:36
   Children eat white powdered sugar doughnuts hanging from strings.
9. Army of Helamin
   Tug of war.