Our Lady of Mercy Secondary School is an all girls public boarding school that hosts students from across Kenya. The school has partnered with Shield of Faith (SOF) for more than a year and is now showing the transformative power of waste management practices in schools.

We began our visit by touring the compost bins and the shambas (“farm” in Swahili), one of which is located near the school’s greenhouse. The original compost bin constructed by SOF was expanded at the request of the school after teachers began to see the real benefits of organic farming and composting–less trash and food waste, improved crops from organic fertilizer, cost savings, and increased student engagement in sustainability practices. SOF has also constructed tower gardens for the 4K Club, which are especially great for water conservation, small spaces, and teaching students about the food cycle.

Teacher Odhiambo, agriculture teacher, shows us the 4K Club’s compost bins.

Right now, the kitchen garden supplements school meals. But Teacher Jacqueline, patron of the 4K Club, said her vision for the shamba is to provide eighty percent of the school’s food supply. This would improve nutrition through organic foods and save the school money. Teacher Jacqueline has been a champion of the SOF composting project and has big plans to keep the school moving towards sustainability.

Gitonga (below) is the school’s caretaker and is one of the reasons for the project’s great success! He manages the day to day responsibilities for the compost and shambas, paying special attention to when and how food waste is put into the bins, compost is turned and distributed, and vegetables are harvested. He also has a famously green thumb! Gitonga fully supports the composting project and is seeing many benefits for the school. In just one year the school has already stopped needing to buy cow manure to fertilize gardens, saving nearly $400 per growing period.

Gitonga standing next to the tower gardens in the shamba that SOF worked with the 4K Club to build. 

Next, it was time to get started on the Demo Farm. The Demo Farm is led by Teacher Odhiambo, who sponsors the Agriculture Club, and is a forum to teach students hands-on farming practices.

We began by prepping the two lots where we would build a Keyhole Garden and a Hugel Mound. The soil on the shamba is very tough because it is a former construction site… this meant Stella had to get very creative about which structures would be the best fit. With the help of the staff and students from the 4K and Agriculture Clubs, we got to work lugging branches and tree clippings, cutting the supplies into the correct dimensions, and assembling the Keyhole Garden. 

All of the teachers came out to see the muzungu doing farm work and decided to chip in.

Students carry buckets of soil to layer onto the Keyhole garden.

Gitonga, Vena, a participant from SOF’s household composting program, and I working on the composting basket for the keyhole garden.

When I asked the students if they could see themselves composting at home, most said that their families live in apartments and don’t have space. I excitedly showed them photos of Stella’s compost tower on her apartment balcony and explained that composting could be adapted to fit their space. When I asked what would help them teach their families how to compost at home, a student responded that some kind of instructions or reference materials would be the most helpful. That’s the heart of this project: making connections between what happens at school and what’s possible at home. SOF is building more than compost bins, they’re building confidence, imagination, and the first steps toward community-wide change.

Stella’s apartment vermiculture composting setup. This structure was designed by Stella and manufactured by a local business.

During a lunch break, Teacher Jacqueline gave a tour of the cafeteria and the food waste sorting process. After students eat, they sort food waste into what can and cannot be composted. The kitchen also sorts food waste as the staff prepare meals for inputs into the compost bins. This represents a mindset shift at Our Lady of Mercy, where waste management has made its way into daily routines. By reinforcing these practices, students and staff are also more likely to retain these habits outside of school grounds. 

Students sorted their banana peels after lunch to put into the school’s compost bins.

Food waste from the kitchen after preparing lunch, ready to be put into compost bins.

After a long day of hard work, we gathered the students to explain how the keyhole garden functions. The structure shows students how to compost and grow food in arid regions or places where soil is too hard. For example, the keyhole garden allows easy access to a central compost basket, where kitchen and garden waste decompose and naturally fertilize the surrounding soil.

Exposure to diverse composting and farming practices are important at boarding schools which house students from across the country, including arid regions like Northern Kenya. [It’s important to note that food waste differs across Kenya. For example, pastoralist communities in the north do not usually have much excess food waste because it goes directly to their animals.]

Students planting and watering vegetables on top of the Keyhole Garden at the end of the day.

The finished Keyhole Garden. The base is built from logs and twigs, layered with hay, grass, soil, and compost which act as a sponge when it rains. Vegetables are planted on top, with compost put in the woven basket.

Stella and Teacher Jacqueline also explained that these are concepts students can bring back home to their parents, friends, and communities. They can be done at scale like schools or farms, or in apartment buildings.

What’s happening at Our Lady of Mercy is more than a school project—it’s a glimpse of what’s possible when communities take the lead on sustainability. Schools like Our Lady of Mercy offer a working blueprint for tackling food insecurity and mounting waste challenges, all while teaching the next generation how to be good stewards of their environment. If we want long-term, transformative change, schools and students aren’t just part of the solution… They are the catalysts.