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From Root To S.T.E.M.: Learning Through Classroom Composting

Updated: Apr 30, 2021

Before we start, we’ve got some freaky stats for you:

Every year, an individual elementary-age student throws away an average of 45 kilograms of food waste. Let’s call this student Steve.

In high school, Steve will go on to throw away 22 kilograms of food waste per year.

Cumulatively, Steve will generate over 400 kilograms of food waste over his school career - not including his university years.

Now, multiply Steve and his terrible waste habits by 503 (which is the average student body in North American public schools.) We’ll let you do the math. But suffice it to say, that is A LOT of half-eaten PB&J’s.

Setting the enormous levels of waste aside, composting is intrinsic to our societal and ecological well-being. Our ability to transform waste into something valuable for our planet is like a sustainability report card: the higher the grade, the longer our planet can provide the resources we require to survive.

And, just like anything else, the skills that build a strong, sustainable society begin in the classroom. As any teacher will tell you, a strong foundation is often the determinant of future success.


The benefits of a school or even class-wide composting system are variable. Some of these benefits can be measured by grade point averages (yes, really), while others can only be measured in a more holistic setting (the child’s well-being, classroom cohesion, positive outlook, etc).

“A growing body of research (...) demonstrates that environmentally sustainable schools can improve students’ academic experience. Green schools have been shown to strengthen academic achievement using a variety of measures, including traditional, standardized test scores.”-The Benefits of Green Schools, Paul Chapman


A large component of STEM education is understanding the interdependent connections between organisms, their various life systems, and how each interacts and effects the ecology to which they belong.

To put it simply: composting helps kids understand the breakdown of life cycles. Example: An apple grows on the tree, is picked, eaten, and then decomposes, and - if all goes to plan - breaks down in the soil, releasing crucial nutrients back into the soil from which it grew and nourishing the various life forms that burrow there.

Composting projects, or an ecologically-based curriculum, will also develop various scientific education skills.

For example, performing a waste audit on your school’s trash collection will develop the students’ abilities in data collection through observation, scientific methodology, proving or disproving hypotheses, cataloging and prioritizing information.

Projects which evaluate the various ways in which food breaks down, including the difference between composting (aerobic digestion) and tossing organic waste into landfills (anaerobic digestion) will require daily observation, evidence collection, sample isolation, monitoring and documentation.

Composting and food recycling is a powerful tool in hands-on learning when used as the catalyst for various science projects and education. The use of real-life problems (waste management and ecology) and materials (leftover sandwiches, apple cores) has been proven to prompt a greater level of interaction with and interest in the curriculum subject matter.


Ah, math. Nearly every student’s worst nightmare.

Composting-oriented projects are an excellent way to combat the students’ inherent apathy when it comes to numbers and signs.

Waste audit projects are an excellent example of this. By isolating the various categories of trash (food waste, paper, plastic, metals, etc), students can determine the ratios of their school’s waste break-down. Ratios, as the bedrock of fractions, can then be developed further to determine ways to reduce waste.


“If our school initiated a food recycling program which reduced our organic waste output by 80%, how would this affect the ratios of waste in our garbage cans if that ratio is 4 parts food to 6 parts inorganic? What would the weight of food waste be if the original ratio was 10 lbs of organics per trash receptacle?”

Teachers have long since determined that real-life scenarios - particularly those that get kids up and moving out of their chairs - are the most successful at communicating lesson plans. Another excellent application of composting and gardening to the maths section of the curriculum is the breakdown of nutrient levels in compost and fertilizer.

Successful gardening requires working knowledge of NPK measurements and the ratios of various macro and micro nutrients in fertile soil. A successful gardener will also need to know how to adjust nutritional requirements per garden plot dimensions.

Example Question:

“A lawn requires 1 pound of nitrogen per 10, 000 square feet of lawn. Our organic fertilizer has an NPK of 20-5-5, and each bag is 30 lbs.

The school garden is (cumulatively) 1, 000 square feet per garden bed, and there are 12 garden beds. How many bags of fertilizer will the school require to properly fertilize our garden?”

This is a real-life issue which gardeners need to master to properly fertilize their plants. It also happens to require advanced reasoning and math skills.

By breaking down this problem into a real-time question and a real-life problem, students will need to perform various equations, multiplications and feats of logic in order to provide an answer - and one which will directly affect the health of their school garden.


A tricky ticket for schools with limited tools and space, engineering and technology is actually a natural extension of creating a usable, sustainable compost pile or tumbler - regardless of location or use.

Compost piles are usually 5 feet squared. Compost bins are typically a large plastic drum or bin, while a compost tumbler is usually an oblong cylindrical container held in a rotating framework (making turning the compost easier).

Constructing or configuring any one of these compost systems requires working knowledge of measurement and interconnected technical and material systems, the uses of various basic tools. Essentially: the more technologically advanced a compost system is, the more an in-depth knowledge of its design will be required to run it.

Example Problems:

  • How to design and install a rotating framework on a compost tumbler?

  • How to ensure sufficient air-flow in a static compost bin?

  • What are the benefits of a horizontal compost bin versus a vertical compost container?

  • How do electric composters accelerate the composting process?

  • How do anaerobic digesters transform food waste into biofuel?

Composting and literacy may seem unrelated at first, but the way these two subjects interact in the classroom is nothing if not intertwined.

Science Fairs

Ah, yes, the main staple of elementary school projects. There’s a reason that Science Fairs have become ubiquitous across public, charter and private schools: they get results.

Students are responsible for selecting a topic, presenting a hypothesis, and then experimenting with their topic until their theory is either proven or disproven. The results are then presented to the school, or the other classes in their grade in a mini-trade show.

The initial points of the project pull on all the skills mentioned above, namely data collection, observation, putting forth a hypothesis, etc.

The presentation side of things, however, puts the emphasis on students’ communication abilities.

How well can a student - who may or may not be skilled in the science portion of the project - communicate through bristol board, images and text, the findings of their project?

Further, how well can that same student verbally communicate what has been learnt thus far, and then written down on paper? How do they animate the 2D of their presentation, to the 3D of their audience?

You may be wondering, how does composting and gardening come into the equation? Well, many science fairs involve organics as the project focus, as growing things are immediately accessible to people: we know about plants, fish and food.

In particular, decomposition is a favorite category for its visual and vaguely repellent subject matter. What would happen if, for one year Science Fairs focused on one particular ecological element: life cycles, for example?

Not only would this help the students who might otherwise struggle with coming up with a subject, but it would prompt an in-depth evaluation of something with real-life consequences for the students.

The process of investigation and presentation would prompt them automatically to become stewards of their local food system. A project focused on composting/food and life cycles will make them actively involved in something that directly affects their parents’ health, their own health, and their future health.

This active involvement would not only lead to further interest in a very important life skill, but would give them the tools to eruditely communicate their opinions and information on the subject. This will prepare them for becoming active participants in their community.

Class “Future”tations

Following the waste audit portion of the Food Savers project, the next step would be for the students to break into teams and select one particular food waste diversion alternative to champion.

Similar to a Science Fair, students would assemble data for and against their own subject and present their findings to the class in either a video, a bristol board presentation, a slideshow, or a performance.

The initial stages would focus on creating mind-maps and brainstorms around their chosen topic, with branches detailing the pros and cons of the diversion alternative. After this phase, the students would then compile a report on their topic and start piecing together a presentation to bring to the upcoming “debate”.

These types of projects exercise the students’ ability to communicate an idea to their peers, to calmly and confidently defend an idea, while also being expected to objectively consider the information put forth by other teams.

Skills like these are irreplaceable in such a gadget-driven world as ours, where students are more likely than not staring at a screen when communicating with their peers. And ecology offers a subject which they can really become passionate about - the earth is their inheritance, after all.

Soft Skills Acquired Through Classroom Composting

“Environmental education also fosters the development of the skills students need to be successful, 21st century citizens, including critical, creative and problem-solving thinking; effective written, oral, and digital communication; and constructive citizenship that nurtures young leaders who can make a difference in their communities.” -Paul Chapman

Ecology & Environmental Stewardship

Connecting with their community will naturally foster a sense of belonging, curiosity and emotional investment. In learning about how their school and their community disposes of waste, and the ecological and financial results of this process, teachers will see kids’ eyes open wide.

“We do what with food?” or “Methane does what to our environment?”

It is rarely the case that children simply don’t care about these issues; in fact, young people are often the most vocal demographic when it comes to protecting the environment and reducing our carbon footprint.

The issue stems from lack of knowledge, and a lack of personal connection. If kids live their lives in an environment which shields them from the processes which underpin their society, how are they supposed to try and change how these processes perform?


Almost any project will foster a sense of belonging and team-building skills. The special thing about composting and gardening projects in particular, is that building community is really an innate aspect of what horticulturalists or sociologists might call “foraging culture”.

Caring for a garden is most successful when it is a social activity. Multiple hands are needed to plant seeds, stir the earth, rotate the compost tumbler, pluck weeds, collect produce and do any of the thousand simple tasks required to grow a healthy garden.

Beyond the menial tasks associated with classroom composting and gardening, the interconnectedness of a garden’s life systems lends a pleasant focal point for discussions about equality, respect, helpfulness, kindness and empathy. An ecosystem requires all elements of the cycle to thrive, just like a team requires all players to succeed.

Hierarchy and individualism is not something a natural environment requires: in fact, if one piece of the eco-machine disappears, this will set off a chain reaction which could result in the loss of an entire - or multiple - species.

Thinking of oneself in these terms can’t help but foster a sense of belonging and empathy - in teachers as well as children. Everyone has a part to play in their own “ecosystem” which is equally valuable and important, and which relies on the success of others as much as the success of the individual.

Positive Living Skills

The average age of skilled farmers has aged with the population. This means that the majority of those people with access to basic horticultural knowledge are well into their fifties, with no “new blood” coming on the scene from the younger demographics.

This is bad news for our society, and bad news for our kids. Not only are we losing a grasp on the means of food production - to which any healthy society should certainly lay claim - but young people are increasingly dependent on “convenience” food, which has been linked time and time again to late-onset obesity, heart disease, cancer, and a host of other health problems.

Knowing how to find, grow, care for and cook your own food are basic skills which absolutely everyone should know. These skills develop a person’s sense of independence, confidence and self-reliance - all considered “areas of difficulty” in many young people today, particularly teenagers.

By incorporating “green thumb” education into the curriculum, we will be recycling basic and irreplaceable information back into our social knowledge bank.

Further, by giving credence to ecology and honouring these extremely important skills in the classroom, this will encourage more young people to pursue degrees in horticulture and agricultural science, to grow their own gardens, to seek and appreciate fresh, locally grown produce and to vocalize their desire for healthy, ethically-sourced food.

Composting and gardening in class is just the first step in a long and winding path: we’d better provide them with the right tools for the journey.

Community Involvement

An important element of the Food Savers waste audit includes investigating existing systems and processes in place for dealing with food waste. This step involves communicating with the janitorial and food service staff, and visiting a waste disposal facility.

While not the most palatable forms of community involvement, understanding where our trash goes is pretty crucial if positive change is going to be made.

The next step involves further investigation into local support, focussing more on any community organics collection services (if any) or on businesses or organizations in the food waste diversion category.

Researching systems of food and waste distribution necessitates taking a pretty close look at the community to which the school belongs. Kids will meet adults which have made food waste their livelihood (however indirectly).

They will understand how waste is a financial and ecological burden - and one which could be lightened, if not eliminated completely through the development of “circular economies.”

By introducing children to the important functions of ecology in their primary years, environmental stewardship becomes second nature for them. They will become the ecologists in their homes and families. They will inform others about recycling and food waste diversion - to a fault!

Placing a child in an environmentally conscious-framework in class sets them on a path toward adopting these values and skills in their later life. “Eco-logic” will become a lens through which to view the world, almost effortlessly.


Brian Clair

7/22/2020, 12:10:31 PM

The craze for STEM Learning has now significantly increased in young students. The universities are coming up with various STEM Learning Programs in collaboration with other institutions & researchers. The STEM Learning Ecosystems have a vast potential to teach the young students in masses. Every year students are applying for these programs in a big number because of the real-time practice and to represent their talents.



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