Learn about the environment and play with mud at the same time!

About the Activity

Wetlands are a hugely important part of our world, because they provide food and shelter to many animals, and protect coastlines from erosion. In this activity, youth will learn how wetlands improve water quality in rivers and oceans using common materials to construct their own model wetland. Through hands-on experimentation, they’ll see how wetlands filter pollutants from runoff water before they enter rivers and oceans.

Grades: 3-5
Topic: Environmental Science
Estimated Time: 45-90 minutes

Brought to you by HughesNet, University of Kentucky Extension & University of Kentucky College of Engineering, Paducah Campus

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You may have some of these materials at home, but you also may need to pick up some art and pet supplies, as well.

  • 2-cup measuring cup
  • 1-cup measuring cup
  • Measuring spoons
  • A strainer
  • Italian dressing
  • A collection of natural materials from outside (sand, mulch, leaves, sticks, etc.)
  • Modeling clay
  • Paint tray
  • Biodegradable paint tray liner
  • Activated charcoal (available at a pet store)
  • Aquarium gravel (available at a pet store)
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Activity Steps

Before we even start our activity, let’s answer this question: What exactly is a wetland?

Wetlands are areas like swamps, bogs, marshes, just to name a few, that have several characteristics in common. First, their soil is typically covered or saturated with water. Second, they provide a habitat – or a home – for a variety of plants, animals and organisms. You can find wetlands all over the world, and on every single continent, except Antarctica.

Now that you know how to describe a wetland, let’s get started on building our own!

Get Outside
If you haven’t already, take some time to collect a variety of natural materials for your wetland, such as sand, mulch, sticks, or any other vegetation that may help to filter your wetland’s water.

4-H STEM Lab - Wonderful Wetlands

Ready Your Habitat
Before we start mixing materials, let’s set up an environment for our wetland to live:

  1. Place the paint tray liner in the paint tray.
  2. Next, let’s use one block of modeling clay create a levee -- or a wall or dam -- toward the bottom of the paint tray’s slope (about two-thirds of the way down should work just fine). This will help to keep your water from overflowing.Tip: Be sure to roll out the clay for your levee until you have a long flat surface, about the size and shape of a ruler. Once you have done this, you can use your clay to divide the tray into sections. Stick each end of your clay wall against the sides of the paint tray to keep it in place.

Create Your Soil
The makeup and saturation of a wetland’s soil is important, because it determines how plants and other living things will grow in and around it.

  1. Before adding any materials to your wetland, it’s important to make sure they are clean. Rinse both your activated charcoal and aquarium gravel in a strainer.
  2. Put 2 tablespoons of activated charcoal – which will represent carbon stored inside the earth – on the very bottom of the paint tray. Feel free to spread it around.
  3. Add 1 cup of aquarium gravel over the charcoal in your paint tray. The gravel will imitate the rocks and stones found on the earth’s surface.
  4. Now it’s time to add your natural filter by placing the elements you collected outside on top of the gravel. The vegetation and mulch you collected will imitate the plants, roots, and other natural elements that you would find in a wetland.

Create Your Water Mixture
Now that you’ve created a habitat for your wetland, it’s time to see what it can do.

  1. Fill the larger measuring cup with 2 cups of clean water.
  2. Add 1 tablespoon of Italian dressing to the clean water in the measuring cup. If you don’t have Italian dressing, you can mix ½ tablespoon of cooking oil, ½ tablespoon of vinegar, and 1 teaspoon of dried spice mix to create your own.

Just Add Water
Slowly pour the water mixture across the top of the slope in the paint tray. Observe what happens as the water runs down toward the levee and reservoir. Does the empty area of the paint tray flood? Or does it stay dry?
Did You Know? The spices in the salad dressing should simulate debris and other large pollutants, while the oil will simulate grease and oil runoff from roads and parking lots. What do you notice about the oil and spices when you pour the water mixture into the wetland?

Bonus Activity (Optional)
Try different combinations of materials to simulate different areas of the wetland, with some areas having more vegetation, some more gravel, etc. Collect the water in the reservoir and pour it through the wetland again. Observe and record what you see this time.

Reflection Questions
Questions for your kids and teens.

  1. Wetlands exist on almost every continent in the world. Which continent do you think does not have wetlands? Why not?
  2. Based on your experience with the activity, what did you notice about the flow of water in the wetland? Did it flood or overflow into the empty area of the paint tray?
  3. Wetlands can help to prevent flooding during heavy periods of rain. Why do you think this is?
  4. Do you think lakes and rivers are wetlands? Why or why not? If you aren’t sure, look it up!
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Investigate and Explore

Wetlands are vitally important to natural ecosystems, but sadly are increasingly threatened by human activities, both directly and indirectly. It is estimated that more than half of American wetlands in the continental United States have been destroyed due to agriculture, construction, and various forms of pollution. Plus, coastal wetlands are threatened by increasingly frequent and potent hurricanes that scientists believe are caused by global warming.

So what can you do about it? One thing you can do is try to reduce the runoff from your own home or property, like fertilizers and pesticides and other trash and pollution that go into storm drains and, very often, into local watersheds that include wetlands. Beyond that, consider donating your time to volunteer with wetland cleanup and restoration projects.

Scenic photo of wetlands

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