You can purchase one of those alligators that grow when water is added.
 As the gator grows, measure, trace, and note observations.  Then when
 he doesn't grow any more, leave him out and let him shrink
 back to original size, measuring him as he shrinks. 

Have the children hunt for short sticks... these will be their alligators.
 Fill a shallow pan full of water for the swamp.  Let each child in turn
 carefully place his or her gator in the water.  Tell the children when
 alligators float in a river, they resemble trunks or logs.  Discuss
 the facts you have learned about alligators.

Provide the children with plastic alligators and
 crocodiles to play in this slimy swamp.

2 cups white glue

1 ½ cups water at room temperature

1 cup hot water

2 ½ Tablespoon Borax

2 mixing bowls

mixing spoons

In smaller bowl, thoroughly blend glue and room-temp water. 
 In larger bowl combine hot water and Borax.  Stir until Borax
 is dissolved.  Slowly pour glue mixture into Borax mixture,
 stirring constantly.  Knead until not sticky.
  Will keep in the fridge for a couple weeks.

Mix shaving cream and green tempera paint and let the
 children play in the mixture with plastic alligators!