Materials required: pictures of wetlands and wetland animals and plants, sponges, cotton swabs, toothpicks, pine needles, pine cones, etc, glue, markers, scissors, cardboard, modeling clay, rasting pan, disposable plastic tray, a jar with muddy water.
Preparation time is probably about 15 - 20 minutes.
This activity is appropriate for all ages.
An entire afternoon visit (1 hour) is good for this activity.

    This may work best if the kids are divided up into small groups, each with a WOODS supervisor. To construct the wetland, complete the following:
    spread clay over half of pan, this represents land (make sure it slopes towards the "water")
    litter it with pine cones and needles, cotton, etc, to represent vegetation, and etch in little streams
    cut a piece of sponge to fit along the edge of the clay land, which will represent the wetland
    Now, pour some water over the environment, and watch how much mud makes it to the "water". Then, remove the sponge, the wetland, and pour more muddy water and make the same observation.
    Discuss this thoroughly with the kids - why did we represent the wetland with a sponge?