William Blake’s famous stanza, “To see a World in a Grain of Sand,” perfectly describes the lessons taught at the Spring Creek’s Recreational Fund’s (SCRF) Aquaponics Lab in PS 346. Students start learning about plant life with just a tiny seed, sometimes no bigger than a grain of sand. Garden Educator, Jacqui Roytman teaches her students that small seeds are a part of a larger environmental concept—the ecosystem.
“An ecosystem is a community of living organisms,” said Roytman. Everyone has a role: the producers, consumers, and decomposers all linked together through various cycles and energy flows. In order to explain and display the vast concept of an ecosystem to a group of third graders, Roytman had her class create mini-terrarium ecosystems. “This project will help students understand the interactions and growth between living and nonliving things in a small environment,” she said.
Dividing the class into several groups of five, each team was asked to describe the various elements plants need to survive, and the interactions between living and nonliving things within the small-scale environment. After supplying the students with containers to represent the miniature world, Roytman handed the students cups of soil, cactus plants, seeds (wheat berries), stones, sticks, shells, leaves and water-filled spray bottles. In addition, she also gave the students model magic clay, so that they can use their imagination and create their own insects, like the Red Wiggly Worms they learned about during their compost lesson.
Mini-terrariums show the students a tangible example of how an ecosystem functions, the process of holocoenosis (the nature of one action creating a systemic change in the environment), and teaches them about fashioning a sustainable environment for a particular plant life. For example, the students are using cactus plants that developed modified leaves to withstand extremely dry environments.
Roytman instructed her class of eight and nine-year-olds to first layer their containers with stones, and then a small amount of charcoal. Once the foundation was in place, they added a layer of soil to fill up about three inches of the container. Students then planted their cactus plant and sprinkled their wheat berry seeds into the soil. “For the wheat berries to grow, we need to make sure the soil is damp, but not soggy or muddy,” said Roytman. She explained that ecosystems should be able to equally sustain a dry plant like the cactus and also allow lush wheat berries to grow.
“During the following weeks, the teams will make and record observations using their journal worksheets, share their observations about the changes they observe between the living and nonliving things with the class, and discuss what is happening in their miniterrariums,” said Roytman. After several weeks, the students will be able to problem solve questions like: Are my plants dying, and if so why? Are they not getting the right kind of nutrients? Is the terrarium too wet or too dry?
Along with their scientific observations the students will also use their imaginations to hypothesize what will happen to their insects. Will the insects and plants co-exist? How will the addition of more organisms effect the miniature environment? Roytman believes that upon the completion of the lessons, the students will be able to understand the concept of an ecosystem and be able maintain a copacetic environment for the plants.
Photo: AKA Hige via Filckr