The Earth Community had two components, water and solid earth, woven together as they are in nature. The water component examined the relationships among rainfall, stream flow and groundwater from both water quality and water quantity aspects. Measurements were made of rainfall volumes and stream flow using simple, inexpensive materials so that teachers (and their students) could visualize and calculate, for example, how much water a one-inch rainstorm actually produced, and what fraction of that input ultimately appeared in a stream. Water-quality studies focused on some easy-to-measure indices such as pH, hardness, nitrate and dissolved oxygen to examine some regional variations in these constituents. Site visits included pristine, impacted and contaminated streams so that both anthropogenic and natural influences on surface-water composition could be documented.
The solid earth component examined the relationships between topography and underlying geology. The teachers participating in the program (Scholars) used topographic and geological maps of their localities to learn the relationships between the two and how they differ from the characteristics of other localities represented within the research community. The goal was to have them collect rock samples with their students during the school year and compare those (via the Internet) with those of the other schools in order to explore the relationships between the kinds of rocks in a locality and its geological characteristics and history. In addition, we looked at the range of topographic features in each locality, such as the underlying geological differences between flat and hilly regions of each site. Map analysis was supplemented by field trips to key areas. This component can also be woven nicely into the water component in order to focus the Scholars' attention on possible geological influences on water flow and composition.
The Ecology Community considered a range of ecological topics but focused especially on the concepts and related issues of (1) biodiversity and the study of plant and animal populations and communities and (2) sustainable agriculture and pest management. Plants, animals, and their interactions are fascinating and easily understandable to even the youngest students and thus provide a rich source of entry points to science as a process and even adventure. The community discussed what and how ecologists study in the natural world and concepts that have motivated research, such as the impact of ecotones (where different types of habitats, such as forests and fields, meet) or the search for nonchemical forms of pest control in agriculture.
One beginning experiment tested the effect of Tabasco sauce, which contains pepper (a natural insect repellent) on the choice of foods by crickets, using a water-only control. A discussion followed on how to do further experiments to see what in Tabasco actually repels crickets. Thus students quickly go from a basic concept in ecology and/or pest control to original experiments on causal mechanisms. Scholars were also given suggestions of a wide variety of animal choice experiments.
Plants are easy to grow in small pots in the classroom and can be used in experiments that mimic the production of agricultural crops and associated research questions. There are many interesting window-sill and seedling experiments such as the search for the optimum level of fertilizers and the use of vinegar to simulate the effects of acid rain. Other experiments developed by the teachers included: testing why you need to scarify seeds, growing sprouts, and finding the best way for growing flowers for sale by a class at holidays (an exercise in research to optimize real production). It is also easy to measure and graph plant growth. Small school gardens allow outdoor crop and insect experiments to test effects of mulches, fertilizers, organic pest control methods, etc.
The Scholars were introduced to a variety of methods to do experiments or sample populations of insects and other animals in the wild (including the school lawns, shrubs, and edges of parking lots). Teachers enjoyed great success comparing insects and insect diversity in a wide variety of habitats (e.g., trees vs. weedy fields) using sweep nets, pitfall traps, and other standard entomological sampling methods, suitably adapted to their grade levels. In addition, they discussed how students could offer choices of foods to other animals that are easily observed: they can watch birds or measure seed loss rates at feeders or offer choices of nuts or feeding locations to squirrels or place food baits for ants. It would also be easy to study plants in nature e.g. dandelions in the yard, trees in nearby woods. The Scholars reviewed the concept of diversity, along with other ideas about the distribution of different types of organisms in different habitats. They were then introduced to the basic techniques of using quadrats and/or transects to sample plant communities in varying habitats. These simple but powerful techniques produce a great deal of data that generates discussion and good opportunities for teaching math skills and graphing results.
The Atmosphere and Energy Community explored the delicate interplay between the atmosphere's chemical constituents and energy input from the sun. These are tied to issues of global warming, stratospheric and tropospheric ozone, and energy sufficiency. Such topics seem almost unapproachable given the dimensions of the problems, but we found a variety of inexpensive and readily available materials that allowed participants to carry out classroom research on them. The Scholars studied the basics of the chemistry and energetics of the atmosphere, the effect of modern human (industrial, energy-use, transportation) activities on the atmospheric balance, and explored alternative sources of energy and energy conservation. And of course, no examination of the atmosphere would be complete without understanding the connections to the earth (acid rain, el niņo) and biosphere (greenhouse gas generation, gaia hypothesis), so we also bridged topics with the other communities.
One of the initial projects in the atmosphere/energy community studied the greenhouse effect through simple modeling using plastic soda bottles, but we opened up the experience to be more than an exercise. The greenhouse chambers designed by the Scholars were wonderfully sophisticated, and allowed them to develop scientific skills to refine their ideas and to isolate variables. To further study the greenhouse topic, we used an inexpensive test for carbon dioxide content, which allowed us to study production levels of this greenhouse gas. The Scholars calibrated this test on their own, incorporating additional procedural and math skills that could be applied in the classroom at the higher grade levels. Many studies developed out of this project: students studied the relative production of CO2 from different automobiles, from human beings, and even from different animals.
In addition, we used a fairly inexpensive chemically-treated ozone test-strip to study tropospheric ozone. The amount of ground-level ozone is connected to the penetration of UV light from the sun, to the presence of certain pollutants, and to atmospheric circulation patterns. This connection allows for a variety of experiments to examine local ozone variations, and to study damaging effects on certain plants, crops, and trees. We also examined more directly technological approaches to passive and active solar energy collection (and related "alternative" energies), and experimented with designs to understand issues of conversion and efficiency. We concluded by applying ideas developed in studying the greenhouse effect to explore models of a "green" (energy-efficient) house by experimenting with different design strategies.