Reduce the amount of food waste that ends up in the landfill through composting at home.
Grade Level:
K-12
Subjects:
Life Science
Energy Flow in Organisms
Cycles of Energy Transfer in Ecosystems
Physical Science
Energy in Everyday Life
Earth Science
Human Impacts on Earth’s Systems
Engineering & Design Practices
Tools & Materials
Scientific notebook/ journal/ paper
Items for building a compost (two options below)
To Do & Notice
1. Question: How do food scraps turn into nutrient-dense soil?
2. Learn:
What is compost? Composting is the process that turns vegetable scraps and other organic materials into nutrient-rich soil.
Watch this video on how compost works: https://www.youtube.com/watch?v=dRXNo7Ieky8. Note: this video refers to food that is compostable in an industrial compost facility, what goes into your home compost may be different!
3. Make a Claim:
What elements do you think you need to break down food scraps? Is it best for the environment to be moist or dry? With oxygen or without oxygen? Does light help or is darkness better? What kind of insects, tiny animals and microorganisms do you think may help in breaking down food waste?
Note down your claim in your notebook
4. Collect Data
Build your own compost:
Option one: Kid friendly DIY composter using a 2 liter bottle:
Option two: Make this worm composter using two 5 gallon buckets with the help of an adult (requires a power tool)
5. Analyze and Interpret Data
Observe your food waste over time and note in your notebook:
Week 1 - what has happened?
Week 2 - any changes?
Week 3 - does the food waste look the same as when you first put it in the composter?
Keep your observations going!!!
What’s Going On
What do you need for good compost:
Carbon: brown materials, like newspaper, leaves, cardboard, paper egg cartons
Nitrogen: green materials (food scraps), like lettuce, carrot tops, banana peels
Oxygen: without air the microorganisms can’t do their job of eating and breaking up the food scraps.
Tiny animals:
What types of composting systems are there?
Vermicompost: Uses WORMS to decompose food waste creating vermicast or worm castings. These castings have been shown to reduce levels of contaminants and create a higher saturation of nutrients than the food scraps had before vermicomposting. (This is ideal for bear and snow country, as it can be inside a garage or house. It doesn’t smell or take up much room!)
Aerobic Composting: Uses air to break down food scraps and organic material. A tumbler compost is an ideal compost system for aerobic composting, as one can rotate the tumbler every few days to add air throughout the compost.
Anaerobic Composting: Anaerobic composting takes almost no effort at all, but takes more time. This type of composting uses time and intense bacteria to break down organic materials. Scraps are put into a compost pile or composter and sit over time. This is not an ideal way to compost as it is not as healthy of a system as it is missing oxygen and produces methane and will begin to stink. This is what happens in landfills.
What do you do with your nutrient-dense soil or worm castings once your compost has completed its decomposition cycle?
Add it to your plants! Inside or outside, plants love the nutrient density of this by-product. Don't have any plants? Find your favorite tree in the forest and feed it some compost. It will love you forever and as we learned from the Talking Trees Snippet, the tree may even share the nutrients with its friends!
Resources
Did you know that the state of California has a composting law? It is called AB1826 and it requires commercial facilities like restaurants, hospitals and schools to recycle their organic waste by composting. To learn more about how our local community is participating and reducing waste visit:
Town of Truckee hosts Compost Drop-Off locations for local residents as well as a Commercial Food Waste Service for local businesses.
Placer County supports organic waste recycling and is working with SWEP to implement organic waste diversion at schools. Visit One Big Bin or Placer County website to learn more about their Organics Recycling program.
Going Further
Learn more about how you can reduce food waste by visiting SavetheFood.com
Grow food from your household food scraps.
Instead of composting everything, you can actually use certain food scraps to grow food! This saves money, the energy and carbon it takes to grow, package and transport veggies to get to you and you can use your compost to feed these new plants!!
Go here to learn how to regrow onions, garlic, ginger, lettuce, leeks and a lot more!
Thanks to our partners at Town of Truckee & Placer County for supporting student’s science & sustainability learning activities.
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