When Kathy Miller's first through fifth graders in Greenville, SC, set out on a spring safari, they were hunting for evidence of animal life in their school garden.
"One of the first sightings my students made were the thousands of ladybugs that seemed to flock to certain garden plants, such as sedum and rudbeckia," reports Kathy. Her keen observers readily hooked by these endearing garden residents, Kathy began a yearlong study of the complex dramas that unfold in a schoolyard ecosystem.
Questions sparked by what students had observed on their "ladybug plants" prompted a discussion of the different stages of insect life cycles. "I had students continue the safari, looking for garden animals at different life stages, drawing them (so we could later identify them), noting where on the plants they found them, and keeping tallies of what they found in each category," says Kathy. (Students were surprised to discover that the brick wall near the class garden hosted a number of chrysalids.) The class observations and data inspired a discussion about the important roles that different insects play in ecosystems. The students' enthusiasm for what they'd discovered even spilled over to the home front. Kathy explains that one student taught his mother that the odd growth on her rosebush was not a disease to be sprayed, but a living chrysalis.
Who's Eating Whom?
That fall, Kathy's students set their sights on who eats what or whom in the schoolyard and garden. "I wanted the kids to think about how energy is transferred from the sun, through plants, to other animals in the garden," she explains. As students puzzled over the feeding hierarchy to determine who were the producers, herbivores, carnivores, and omnivores, discussions and research flourished. Hand lenses readily revealed that caterpillars were the culprits who munched on leaves. Keen observers noted that milkweed provided food for aphids, which in turn were consumed by lady beetles. "The students examined who was caught in spiders' webs, discovered what different birds were eating, and followed toads' travels," says Kathy. She explains that if they couldn't actually find evidence of what an animal, such as a praying mantid, ate, the students first speculated based on their observations, and then consulted resources, such as encyclopedias.
Next, Kathy had students dig into their data and draw simple food chains, beginning with the sun, using arrows to indicate how each plant or animal provides energy to the next in line. "Once the students had created food chains, I had them re-draw two or more chains and consider how they connect to one another to form food webs," says Kathy. The resulting works surely enabled Kathy to assess students' grasp of the concepts they'd explored. But there were other gains too. "By harnessing the students' curiosity and excitement, this project greatly nurtured their respect for nature and their desire to learn more about it," she explains.