Make Your Own Compost!
Student challenge. Americans generate approximately 250 million tons of trash each year. Did you know that approximately 57% of this goes into municipal landfills? According to the U.S. Environmental Protection Agency, landfills emit nearly 6.3 million metric tons of methane into the atmosphere, and this is very harmful to the environment. But you might be surprised to know that waste such as scraps of vegetables, pieces of paper, and coffee grinds can be used to make compost, which can provide valuable nutrients to our gardens and farms.Your school has hired you to work as a team of scientists and engineers to help design a composting program so that the amount of waste going into landfills is reduced. You will work in teams in your science classes to research ways to make the best compost, and prepare a podcast for your school’s principal advising him or her on designing a composting program, and help make this a reality in your school.
For this challenge, students will work in groups and investigate the science of compost as an ecosystem (food webs, producers, consumers, decomposers and their interdependent relationships, living and non-living parts of an ecosystem, flow of matter and energy, etc.), and generate questions about the various factors that affect the production of compost. These questions will drive their research on the SciViz etextbook (described later in the proposal) to learn about the compost ecosystem. With the information they gather, students will design experiments, manipulate variables, and observe and measure outcomes to test their hypotheses about how factors such as types of containers, amount of light, nitrogen to carbon ratio, levels of oxygen, temperature, and amount of water affect their composting ecosystem, through a series of experiments in their soda bottle bioreactors. Students will also calculate the volume of the waste generated in the school, research the type of composter needed to keep the compost aerated, and generate a list of questions for experts in bio-engineering to answer.
Classroom learning will be strengthened by parental and community involvement. Students will use a checklist of materials to bring from home each week. They will discuss with their parents the materials that they are taking to school for their soda bottle bioreactors, and explain the science of composting. To involve the community, we will organize virtual meetings with personnel from the community–e.g., an official from the county’s waste and recycling program and a bio-engineering scientist from the nearby university ((UW, UNC orAuburn)––with whom students can engage in discussions and ask questions. The capstone activity of this unit will be the conceptual design of composters needed for the school. Students will also prepare a podcast to the principal of their school, explaining the benefits of compost, the science of making compost, and advise him/her on starting a composting program in their school. All podcasts will be available on the project’s website.
Algae Power Plant!
Student challenge: Are you aware that in the last century, quantities of greenhouse gases have significantly increased in our atmosphere due in part to our activities, such as burning fossil fuels, negatively impacting the health of our planet? Did you know that biofuels generated from plants and algae are a desirable alternative to fossil fuels because biofuels can result in negligible harmful emissions? The next generation of scientists and engineers face the challenge of producing safe, affordable, efficient, clean, and abundant sources of renewable energy in smaller amounts of space. Your challenge is to design an “algae power plant” to (1) produce high quality and quantities of oil (biofuel) in a small amount of space, and (2) maximize photosynthetic processes to minimize energy inputs and maximize energy outputs. Based on your findings, you will write a letter to a local transportation company explaining how bioenergy can be incorporated into their operations.
To address this challenge, students will engage in procedures and routines similar to those described in Example 1, and learn about fundamental plant processes such as photosynthesis, energy transfer, energy conservation, and energy flow in and out of organisms. Working with readily available materials such as different kinds of algae, soda bottles, water-based nutrient solutions, and different light sources, students will manipulate external conditions to understand how the amount of nutrients in water, levels of light, growth period, and temperature variations affect the oil production in their algae power plant using different species of algae1. An exciting extension of the challenge into the realm of engineering is that students will then use the oil to power a toy steamboat and measure variables such as the distance the boat travels and its speed as the oil is burned and discuss their findings with a scientist from the university.
Grow Healthy Plants!
Student challenge: Did you know that invasive species, bacteria, pests, and factors such as climate change affect plant growth and the amount of food they produce? This is a big problem because the natural resources (land, water, clean air, etc.) that we rely on are limited and decreasing, but the need for growing more food is increasing. To help address this issue, your challenge is to design optimal growing conditions for Fast Plants in a given environment that will result in maximum seed production. Students will design and experiment with several habitats for Fast Plants to understand how seed production (reproductive success) is affected by environmental and genetic factors. Fast Plants are a variety of Brassica Rapa (the crucifer family of plants) developed at the University of Wisconsin. Their rapid growth makes it possible to complete an entire life cycle (35 days from seed to seed) during a typical science unit. They are an excellent model of genotypic and phenotypic diversity in a population and how this diversity is influenced by environmental factors because they are (1) a diverse species that exhibit a variety of genetic traits that can be easily controlled during reproduction because they do not self-pollinate, and (2) highly responsive to limiting factors present in environmental conditions due to their rapid growth rate. Students will learn about processes of growth and development of organisms, variation and inheritance of genetic traits, and change in populations.They will engineer and experiment with different habitats, controlling for lighting, soil, water, etc., for Fast Plants in order to understand how different environmental and genetic factors influence seed production, with Fast Plants experts from UW serving as valuable online resources for students to consult.