We have a lunch compost program at our school. Grade 6 students volunteer in the lunchroom to help younger students remember to compost their leftover fruits, veggies, and napkins. The volunteers also weigh and chart the compost before emptying the lunch scraps into our three-tier compost bin.
When I met with 6th grade students for the first time, I invited students to tell me what they know about the lunch compost program. I am new to the school, and was curious about how it works. The students described the process and explained that the compost is used to fertilize their school garden. When I asked the students how the food turns into fertilizer, they realized they didn't know.
A few students raised their hands and tried to guess. One student thought worms were important because he had seen a compost that used worms before. He said maybe the worms break down the food. (They eat it and poop it out?) Another student said time was important. It takes a long time for the food to break down, and maybe heat from the sun was needed. But students were mostly stumped. They added a question to our question board: "How does food break down and turn into fertilizer?"
Next I asked the students if they'd like to see the compost bins in the back of the school. While most students knew the compost bins existed, they had never seen them before. So we went outside to make some observations. We observed that fruit flies were all over the fresh lunch. When I opened the middle chamber door to examine the older soil more closely, tons of worms started pouring out. This got quite a reaction from the students! We now had evidence that worms ARE important for decomposition!
When I met with 6th grade students for the first time, I invited students to tell me what they know about the lunch compost program. I am new to the school, and was curious about how it works. The students described the process and explained that the compost is used to fertilize their school garden. When I asked the students how the food turns into fertilizer, they realized they didn't know.
A few students raised their hands and tried to guess. One student thought worms were important because he had seen a compost that used worms before. He said maybe the worms break down the food. (They eat it and poop it out?) Another student said time was important. It takes a long time for the food to break down, and maybe heat from the sun was needed. But students were mostly stumped. They added a question to our question board: "How does food break down and turn into fertilizer?"
Next I asked the students if they'd like to see the compost bins in the back of the school. While most students knew the compost bins existed, they had never seen them before. So we went outside to make some observations. We observed that fruit flies were all over the fresh lunch. When I opened the middle chamber door to examine the older soil more closely, tons of worms started pouring out. This got quite a reaction from the students! We now had evidence that worms ARE important for decomposition!
We took a sample of soil from the compost. Then we moved to the garden to make more observations. We compared the garden soil to the compost soil. I invited students to search the garden to see if they could find decomposition happening. They discovered a pumpkin and a squash decaying. They also discovered what they called "mold" covering the leaves of one of the zucchini plants. I asked them if they thought mold was important for decomposition. They agreed that mold did play a role in the decomposition of food. We are going to keep thinking about mold. What is mold?
When we returned to the classroom, I invited students to work in small groups to design an experiment that would answer some of our questions about decomposition. I provided each group with a potato and three test tubes. I didn't give them much more guidance than that because I wanted to see what they were capable of on their own. Overall, I was impressed by their good thinking!
When we returned to the classroom, I invited students to work in small groups to design an experiment that would answer some of our questions about decomposition. I provided each group with a potato and three test tubes. I didn't give them much more guidance than that because I wanted to see what they were capable of on their own. Overall, I was impressed by their good thinking!
One group tested the effects of temperature on decomposition, and another tested the effects of dry vs. wet soil. I had groups compare the rate of decomposition with and without worms, or with and without fruit flies. I had a group compare how a potato vs. yogurt decomposes. (They were curious why you can't put dairy or meat in the compost bin.) I have another group who asked to test the effects of salt and vinegar on decomposition. So I found some vinegar and salt in the cupboard and let them have at it. We had quite the variety of experiments!
Two weeks later, students emptied the contents of their test tubes to make observations and record the results in their science journals. As you can imagine, our classroom quickly became very stinky! But students learned a lot about decomposition, and generated further questions for us to study. The question of the day was: Why does decomposition stink so bad?
Two weeks later, students emptied the contents of their test tubes to make observations and record the results in their science journals. As you can imagine, our classroom quickly became very stinky! But students learned a lot about decomposition, and generated further questions for us to study. The question of the day was: Why does decomposition stink so bad?
I invited a professional gardener to visit our classroom to teach us more about composting. We asked Mrs. Marvel if compost is supposed to stink. She says no. She taught us what we can do to reduce the stink at our compost bins. We need layers! Students volunteered to bring grass clippings, dead leaves, and chicken manure from home. We will continue to work on our compost over winter in preparation for spring planting.
We identified microorganisms as the main source of the stink, and had a group discussion about the role of microbes as decomposers in our environment. How can we learn more about microorganisms? We will start by learning how to use a microscope. We want to see what microorganisms look like. But where can we find microorganisms to look at? We will keep thinking.
We identified microorganisms as the main source of the stink, and had a group discussion about the role of microbes as decomposers in our environment. How can we learn more about microorganisms? We will start by learning how to use a microscope. We want to see what microorganisms look like. But where can we find microorganisms to look at? We will keep thinking.
Meanwhile, Mrs. Marvel helped us plant our fall crop of kale, spinach, peas, and carrots. We purchased compost and manure for fall planting. It cost us $65 and filled only two garden boxes. But come spring, we should have our own homemade compost from garbage...for free! Thank you microorganisms! (Decomposition is so cool.)
I love these photos of the students' hands in the soil. The warm, crumbly soil felt so good between our fingers. Interestingly, the store-bought compost we mixed together didn't stink. It smelled good, like earth. (Why is that?)
I love these photos of the students' hands in the soil. The warm, crumbly soil felt so good between our fingers. Interestingly, the store-bought compost we mixed together didn't stink. It smelled good, like earth. (Why is that?)