In Carroll County, a 300-acre lake, filled with fish and surrounded by wildlife, is a living classroom, providing lessons more memorable than any gleaned from a microscope or textbook.
For the bio-communities science unit, teachers are taking their classes to Piney Run Lake near Eldersburg, an ideal setting for studying the delicate web of life, the interdependence of animals and the role humans play.
The "lake study," designed for fourth-grade pupils, has children combing the shores for tiny specimens and riding a pontoon boat to search for trout and beaver.
Class starts at Piney Run Park Nature Center with a food web game, with children adopting the identity of animals and plants. They weave gold-colored yarn -- the color of sunlight -- into an intricate food chain that starts with tiny plants and insects and ends with herons, otters and widemouth bass.
"We look like a giant spider web," said Samantha Kretschmer, who participated in the study Tuesday with her classmates from Winfield Elementary School.
"You are all connected by strands of sunlight," said Deanna Hofmann, a park naturalist who was leading the class.
The children giggled as classmates read descriptions of bugs that "can slurp fish like soup."
But when Hofmann asked what would happen if too much lawn fertilizer fell into the lake, the game took a serious turn.
"Drop your string, if you are a bluegill or a bass," she said. "What is happening to our food?"
"It is dying," said the children.
"The idea is to show how different animals depend on each other and how people fit into the picture," said Hofmann, who leads about 60 such programs each year. "This is an experience they could not have in a classroom."
The class collected a water sample and took it back to school. They viewed it under the microscope yesterday. The samples showed good water quality and were filled with interesting specimens, said JoAnne Stevens, their teacher. "We can always get pond water, but it is not the same as actually being at the lake and seeing," Stevens said.