Leap Frog
Have your children all line up and squat down. You can then have them play the
classic game of leap from while yelling "L" or "Leap" 
Turtle Ritz
Put peanut butter on Ritz crackers and let your children use pretzels to make
the legs and tail of the turtle.
Pantyhose Snake
During reptile week put pantyhose snakes in the play are. They're easy to make
just put tissue in one leg of pantyhose. Add your own facial features to make
the snake look more real.
Feed the crocodile
Draw a large crocodile face on a piece of poster board or the side of a box.
Cut a hole out where the crocodile's mouth would be and add paper teeth (make
it at least twice the size of the beanbag). Tape the board to a chair and let
each of your children take three tries to feed the crocodile (by throwing a
beanbag into the crocodile's mouth).
Alligator Snack
Get alligator meat from your local grocery store or specialty food store. Have
your children tell you if they like the taste and graph their opinion