Once students have some experience working with a basic terraqua column (see the Terraqua Columns Lesson), they have an opportunity to design and conduct their own investigations with their mini-ecosystems. There are hundreds of variables students can manipulate with a minimum of materials – temperature, light, pollution, type of water, type of soil, etc. As a class, students brainstorm variables that might affect the plants, soil, and/or water in a terraqua column. In teams, students propose a project, and once approved, set about testing their ideas and observing the effects of their manipulations on their mini-ecosystem. If your school participates in a local science fair, this is a fantastic activity to introduce students to experimental design, variables, and control groups.
Can use a lab notebook to design experiments, make observations, and draw conclusions.
Can design an original experiment.
Can explain what an experimental variable is.
Can explain the reason you need a control group to compare against.
Can keep track of and organize observations over a long period of time.
Can draw conclusions from results.
Can make connections between small scale models and real world events.