I’m a big fan of composting, and my kids know it’s an important part of our family habits. But do you know why it’s so important? Do your kids know why composting matters? Try this experiment to see why we should compost our food scraps so they don’t contribute to climate change.
Teaching our kids to practice sustainable living habits is really important, and it can be really fun. Also, as our kids get older, it’s helpful to explore with them why sustainability and eco-friendly family habits matter.
We can teach our kids about the science of sustainability and the reasons it’s so important through a variety of projects, books, and other forums and channels. One of my favorite ways to teach my boys about eco-friendly principles is through mini at-home science projects.
A couple of weeks ago, I teamed up with one of my very favorite Instagram and YouTube teachers, Jess of Thoughtfully Sustainable, to share three sustainability science experiments you can do with kids at home over on Kathryn Kellogg’s blog, Going Zero Waste.
We talked about the food waste audit my family and I did a few months ago. We encouraged families to try growing food from food scraps.
We also introduced this landfill decomposition experiment, my favorite experiment of the three. This experiment shows young scientists how food scraps decomposing in an environment without oxygen, like a landfill, create gas. This is in comparison to food scraps that decompose with oxygen in a healthy composting environment and instead release oxygen, water, and a bit of carbon dioxide.
In a landfill, anaerobic decomposition (or decomposition without oxygen) releases methane gas which, according to the Environmental Protection Agency, is approximately 25 times more potent than carbon dioxide with respect to trapping heat in our atmosphere and contributing to global warming.
In other words, this experiment shows our young environmentalists that properly disposing of food scraps in a compost bin instead of a trash bin, where food scraps may end up in a landfill, can significantly reduce each person’s individual impact on greenhouse gas emissions.
Perform the Landfill Experiment
To perform this experiment, partially fill three of the four containers with food scraps and then fill each container to the top with water. Fill the fourth container with only water. This will be the control for the experiment.
Cover each bottle with a balloon and seal the edges of the balloon with tape if they are not especially tight. For more formal instructions that include scientific explanations and more precision, I’ve included detailed instructions below as well as a link to the original source. My boys are young enough that we didn’t need to execute the experiment with much precision, but the original experiment instructions might be helpful for older students or teachers looking to use the experiment in a classroom.
Over the course of a few days or a week, some of the balloons should begin to blow up as the food scraps decompose and produce methane gas. The balloon over the bottle filled with water should not change as there is methane production and thus no gas to fill the balloon. See the How-To instructions at the end of the post for most specific details.
You can this sustainability science experiment (and the other two we shared on Going Zero Waste) with kids. They require minimal preparation and a few materials you probably already have at home. Let me know if you try them out and what you think!
Thank you so much to Jess of Thoughtfully Sustainable for all her science and teaching experience. Go follow her. You won’t regret it.
- 4 bottles (glass bottles or reused plastic bottles)
- 4 balloons (Mylar preferred, Latex will work)
- Fruit or veggie scraps (3 different types)
- Water (enough to fill all four bottles)
- Funnel (optional)
- Crush or puree food scraps. We used bananas, blueberries, and onions because that's what we had on hand.
- Add each type of food scraps into its respective bottle.
- Fill each bottle, including the empty bottle, to the top with water.
- Cover each bottle with a balloon. Tape edges of the balloon to the bottle, if desired, to prevent gas leakage.
- Allow the bottles to sit for several days and observe some of the balloons filling with air.
Project adapted from Education.com