Carlisle Grows Green FAQ

 This FAQ is a work in progress.If you have a question about Carlisle Grows Green, the garden or the compost project, please submit your question by contacting us through the project website:


How did composting get started at our school?

The composting project was suggested in the spring of 2009 by 6thgrade students, Caroline Crouse and Caleb Perlman, after their 6thgrade Outdoor Camp experience. As part of the Outdoor Camp, students weigh and survey their trash. Seeing how much food was wasted during camp got them thinking about the food waste from school lunches, an everyday occurrence.

Caroline and Caleb felt a school-wide composting program would be a good way to address the food scrap waste issue and that such a project was a concrete way to apply what they were learning to daily life at school. They presented their idea to the School Recycling Committee and pursued the idea further by contacting Launa Zimmaro, a member of the Carlisle Household Recycling Committee.

As of October 2011, over 90 students in grades 2-8 have volunteered to participate in the program as members of our student ‘compost crew’!

For a more detailed overview of the project’s development from 2009 to 2011, refer to The History of Carlisle Grows Green, 2009 - 2011 found in the About page on the website project homepage: 


How does composting benefit our school?

Composting is beneficial environmentally, educationally and economically. 

Environmentally, when food waste is composted, all the residual nutrients of the food waste are converted to nutrient rich, healthy soil referred to as compost. Compost is called “black gold” by many gardeners because when it is added to planting beds and lawns it enriches the soil and promotes the growth of healthy plants.

Additionally, by composting food scraps, a much higher percentage of the residual ‘energy’ in the scraps is recovered in the end product of compost rather than wasted through disposal. This is true even in the case of ‘waste to energy’ facilities. 

Back yard or local composting also saves the energy (fuel) required to haul, transport and then bury or burn it for disposal.

Composting enriches rather than pollutes the environment. Landfills emit large quantities of methane, a powerful greenhouse gas. They also ooze leachate. Leachate is a byproduct that often contains toxic elements that can filter through the soil and into waterways. Items thrown into landfills take many years to decompose and a great deal of landfill material never decomposes. Incineration also results in emissions that pollute our air, soil and waterways. Air pollution is closely linked to many respiratory health issues.

 The EPA and leading scientists state that greenhouse gas emissions pose a serious threat to the environment. Composting is a meaningful contribution that each of us can make to reduce rather than increase this problem.

 Educationally, composting helps integrate learning in school (e.g., Outdoor Camp) with life in an authentic, meaningful application. Teachers also use the compost and the garden as natural ‘labs’ where students can apply science and math skills. The project can also be an inspiration for artistic and literary expression and stimulate new learning associated with the food cycle, the environment and a host of other topics and interests.

Composting costs the school district and families nothing and could potentially result in a direct economic benefit to the town and the community. The Carlisle School hires a waste management firm to haul waste (referred to as a tipping fee) from school to a site for disposal. The current school contract is based on a minimum number of pick-ups per year for a specified container size.

Our spring 2011 waste audit revealed that the school cafeteria generates an average of 65 pounds of food waste a day. Through composting, we have reduced the number of filled trash bags during lunch by 25-30%.

With this level of trash reduction, School Facility Manager, David Flannery, estimates a theoretical savings of at least $800/year. Hauling data is being tracked to determine if disposal contracts could be modified for cost savings in the future.           


What does it cost to run the composting program?

It costs the school district and town residents nothing to implement the composting program. The project is completely self-funded through grants, cash, and in-kind donations. The project does not involve extra staff time for implementation.


Who is in charge of the composting program?

The CGG project team consists of parents, staff (teachers, administrators, the Food Services Director and Facility Manager) and residents. A core group of 6 adult volunteers (staff, parents, community members) are part of a planning team that works on program development and implementation.

The three founding members of CGG are parent and Master Gardener certified Kathy Balles, K teacher Mimi Chandler and town resident/Household Recycling Committee member, Launa Zimmaro. This group shares oversight responsibility for the project. All major decisions related to the project require approval from school administration, and administration is frequently consulted and informed of various aspects of the project. Launa is currently acting as Project Team Facilitator and is responsible for project related print communications and outreach.


Are CGG team members who work directly with students required to go through a CORI review?


In what ways are students participating?

Students participate every day when they sort their own recyclables, trash and food waste. More direct involvement is available for students who would like to work as part of the student composting ‘crew’. The composting crew teams help with indoor and outdoor tasks related to the project.

Student volunteers in grades 2- 8 are eligible to help with indoor tasks.

Indoor tasks involve making sure the sorting counter is ready for the next lunch. This involves checking the small recycling barrels to make sure cans and bottles are separated, carrying the flatware basket and liquids bucket to the washing window and replacing them at the counter station after they’ve been washed by kitchen staff. The liquid buckets contain water, juice or soda emptied from recyclable containers which can be recycled only when empty.

Student volunteers in grades 3-8 can be involved with outdoor tasks. Outdoor tasks involve carrying the compost buckets to the compost bins, emptying the scraps in the bin, spreading “browns” (e.g. leaves) over the scraps, refilling the browns bin for the next crew and returning empty scrap buckets to the cafeteria. Different students take on each of these roles so they are all happening simultaneously.

The indoor and outdoor tasks described above are performed every school day.

There are also weekly and monthly task crews for leveling (once a week) and turning (once a month). Several 8thgrade students have volunteered to level and turn for community service credit. Adults are also available to help with leveling and turning as needed.

There is no part of the program that requires physical contact with the compostable scraps or liquids, however gloves will be provided.


How many children will be going to the bin at a time?

Up to six students may be involved depending on the needs of specific lunch periods.


Do the teachers and other staff at the school participate in composting efforts also?

Teachers haven’t been asked to compost classroom food scraps, but several of them do.


Does the kitchen staff participate in composting?

Yes. In fact, School Food Services Director, Sue Robichaud, voluntarily began composting food scraps in the spring of 2009 and personally carried kitchen food waste to the compost bin after lunch. The Carlisle DEP provided a small backyard composting bin for kitchen use prior to the installation of the permanent bin. Kitchen scraps are now added to the food scrap buckets in the cafeteria on a daily basis.


How is odor controlled?

When compost piles are properly “fed” and maintained there is little to no odor. The key to a healthy, odor free compost pile is the ratio of carbon (browns) to nitrogen (greens), moisture and aeration. The slight, temporary odor that occurs normally during leveling and turning dissipates quickly.

After our trial period last year resulted in a 2-3 week period of ‘smelly’ compost, we addressed the problem by increasing the carbon:nitrogen ratio and frequency of ‘turning’.

We use a ratio of 2-3 parts browns to 1 part greens as recommended by composting experts. This means that for every bucket full of food scraps, we add roughly 2-3 buckets of browns to completely cover the food scraps.

The browns we use consist of chopped straw, old leaves, wood shavings stored outside and brown paper napkins and ripped paper bags from lunches that go into the composting buckets along with food scraps during sorting.

While meat, fish and dairy can be composted successfully, their addition can make it more difficult to control odors. Therefore meat, fish, cheese (other than pizza topping) or other dairy products are prohibited from our composting program as an added odor control measure.

To find out what is and isn't composted in the Carlisle School Program, go to Do's and Don'ts located on the right hand side of the homepage above the Blog.


Will compost crew volunteers lose class or recess time?

The indoor and outdoor tasks happen during the last 5 minutes of the lunch period. Compost crew students will be able to go to the head of the lunch line to get an early start on lunch.

Indoor task crew members get in line with classmates in the cafeteria to go back to their classes. Outdoor task crew members remain at the bins with adult supervision to join their classes outside as they exit the building and head back to class.

Timed trials have demonstrated that after training, the tasks can be completed comfortably within a few minutes and in time to go back to classrooms with classmates.


Who escorts the young children back to class?

All of the compost crew students (grades 2-8) will join their classes to return to classrooms during the regular return process. They’ll be escorted by their teachers or designated aides or other staff along with the rest of their classmates.


How do teachers/staff feel about the late-comers entering class as a result of crew duties?

No teacher or parent wants their child to miss class time. Neither do project volunteers. As described above, the formal program is designed to ensure no lost class time or late class entries.  


How do students become volunteers?

At the start of the school year, students who want to volunteer sign a classroom sheet listing their name, grade and classroom teacher. Parent consent forms are then sent to the parents of those students. In order to participate, students must return a signed consent form to their classroom teachers. Once the signed consent is received, students can participate.


What is done with the compost from the bin when it’s full?

Some of the finished compost is used to supplement and enrich the school vegetable and herb garden beds behind Corey Auditorium. The balance could be used in landscaped beds on school grounds.


Is the compost available to the public?

At this point, we don’t know how much extra compost will be available. This is a TBD item that will be explored after a full year of the program.