"Exploring life in the river near our school intrigued my third and fourth graders," reports Waits River, VT, teacher Cheryl Ollman. "But, of course, the time for working outside is limited by our climate. When I discovered that a local educational group was experimenting with an indoor river simulation, I volunteered to test it out in my classroom."
In preparation for creating a classroom river, Cheryl's students generated a list of things they knew about river life and things they'd like to investigate and do with the classroom river. Their goal, she says, was to try to develop a model of the outside river so they could examine plants, animals, and their interactions throughout the year, and explore how changes might affect their in-class ecosystem.
With support from local environmental educators, the class constructed the river system in a day for about $200, using plywood, PVC pipe, washtubs, and a submersible pump. The 10-foot-long by 3-foot-wide system begins with a "marsh" in a tub under GrowLab lights, flows into the river, then empties into a "pond" with a pump.
Students used water from the real river behind their school to supply their indoor ecosystem, replenishing it as the level dropped from evaporation. To create the marsh, during the fall they transplanted dormant reeds, grasses, and cattails right from the school's pond. "The kids were incredibly observant," reports Cheryl. "They loved to be the first to notice new forms of life: emerging caddis flies, new plant shoots, different types of algal growth."
Students kept track of pH in different sections, identified life-forms, documented plant-animal interactions, and tried to solve problems that arose. For instance, when students first noticed an oily residue on the water, they speculated where it may have come from, and tried several techniques to get rid of it. "Students finally noticed after we'd put in the marsh plants that the oil seemed to dissipate, and wondered whether the plants had helped," Cheryl notes. Follow-up research on wetlands' roles as biofilters supported their hunch.
Now that students have gotten their feet wet, Cheryl adds, they want to try simulating some real-life problems, like agricultural fertilizer and manure runoff, to see what impact such factors might have on their classroom river.
"The students have a much more solid understanding of how an outdoor system works now. They can appreciate that a river system teems with organisms interacting and affecting one another," says Cheryl. "Probably the most significant outcome was the motivation and enthusiasm sparked by the kids' ownership and investment in the project, from the initial designing and building to troubleshooting problems."