Garbology

Key Topics/Vocabulary: Decomposition, Decomposers, Composting, Prediction, Organic Matter, Fertilizer

Grade Level: 3rd - 6th

Click here for #3 Series Description

Spanish Lesson Plan

Science Framework

Lesson Video

Lesson Bridge:

Connect this lesson to Taco ’Bout Plants (2) by asking students to think about which types of waste break down in nature and which don’t. Do the six plant parts break down? Bring the lesson full circle by explaining how compost made from plant parts gives nutrients back to the soil, helping new seeds grow even bigger and stronger.

Lesson Overview:  

In this lesson, students will explore which types of materials can break down, or decompose, over time. They’ll conduct a simple experiment by sealing different items in a bag with soil and observing what happens over a month. Students will: observe how items change as they decompose, identify patterns in what breaks down and what doesn’t, and explain how matter changes during decomposition.

Suggested Activities and Learning Objectives by Grade:

• 4-PS3-2: Make observations to provide evidence that energy can be transferred from place to place by heat

• Energy can be transferred in various ways and between objects

• 5-LS2-1: Develop a model to describe the movement of matter among plants, animals, decomposers, and the environment

Essential Question(s) that Connect CCCs and SEPs:

• How can we set up an experiment to see what things decompose and what things do not?(Asking questions & defining problems)
• How do you think the items in our experiment will change over time? (Stability & Change; Planning & Carrying Out Investigations).
• What happens to the energy in plants when they start to decompose?(Energy & Matter; Asking questions & defining problems)
• Do you think decomposition will cause some of our solids to turn into liquids or gasses? (Energy & Matter; Stability & Change; Asking Questions & Defining Problems).

Vocabulary:

Decomposition- To breakdown or be broken down into smaller parts, especially by the act of living things.

Decomposers- A living thing that feeds on and breaks down plant and animal matter

Composting- An easy way for us to turn food waste into rich soil to grow healthy plants in.  

Prediction- An educated guess, the act of saying what might happen in the future.

Organic Matter- Matter that has come from a recently living organism.

Fertilizer - A substance containing elements that help plants grow and used by farmers and gardeners.

Materials:

• 5 gallon bucket (or similar sized receptacle)
• Some sort of lid for the bucket that will allow air to come in (an old t-shirt or bag with a bungee around it works well).
• Healthy, moist soil
• Spray bottle or hose with spraying nozzle
• A variety of compostable, recyclable, and disposable items (best if acquired from the foodbank or from your garden/school)
• Biodegradable Tape and Sharpie
• Wanted FBI Worksheet (optional)
• Series #2 Garden Journal (optional)
• A scale (optional)

Prep:

• Have a plan of where you want to leave your bucket of compost. Ideally, it will be placed somewhere in the shade to avoid drying out!
• *Optional - Look for a fun book on decomposition/composting to read to the class. Reach out to your school’s librarian to see what’s available.

Activity Procedure:

Engage:

Have you ever seen food spoil or go bad? What did it look like? What do you think was happening to it?

Sentence Frame: We _________ to turn food waste into rich soil. (compost)

Explore:

Take a look around the garden and see if there are any plants or leaves that look dead. Let students observe them and ask them what they think will/is happening to them? How is decay part of the cycle of life? While in the garden, let each student pick something natural off the ground (not off of a growing plant) to use in the experiment and then return to the tables for an explanation.

Option: Visit your worm bin to explore!

Explain:

Write the following underlined questions on your board and record student answers:

What is decomposition?

Follow up:  Decomposition is a magical process! It is also called rot. It is the result of billions of tiny invisible life forms such as bacteria and fungi as well as some larger decomposers like worms and other bugs that break down organic matter. These decomposers are often called the “FBI:” fungus, bacteria and invertebrates.

        Thumbs up/down: Have you ever seen mold before?

The FBI helps to break down dead plants and animals into smaller particles called compost, by eating it!

Think, Pair Share: What would happen if we didn’t have any decomposers?

 (Without decomposition, dead matter would cover the earth and we wouldn’t have the necessary nutrients for new life to grow!)

What is a prediction? 

Follow up: A guess of what will happen in the future based on observation, experience, or scientific reason.

Action:

Compost in a Bucket/Bag

1. Place all of the student's items into the compost bucket. Make sure to add some items that will not decompose such as wrappers/packaging. Note: If you wish to get weight so you can see the difference in before and after weights, first have students weigh themselves with an empty bucket and then subtract this from the weight of the bucket containing items.
2. Add a little bit of fresh soil and explain that one tablespoon of good garden soil has 1 billion bacteria in it!
3. Let students take turns spritzing the bucket with water.
4. Attach a lid to your bucket that will keep critters out but let some air in.
5. Place the bucket in a shady spot in your garden or shed.
6. Use masking tape and Sharpie to date it.
7. If necessary, label it with the teacher’s name or room number to distinguish it from other classroom experiments.

Reflect:

What do you think will have changed in the bucket in a month? Raise your hand if you have a prediction you’d like to share with the class. What items do you think will not decompose - why? If they don't decompose in our experiment, do you think they will decompose in the environment? 

More lesson Photos

Extension Activities:

• Ask students to do research on decomposers, pick their favorite decomposer, and then write and draw a cartoon strip of them hard at work in the compost pile.  
• Go out to the garden or worm bins to observe decomposers.
• Have students fill out this compost-in-cup worksheet
• Classes can adopt a space in the garden and conduct a composting experiment to test if compost helps plants grow.  Follow this guide: What Good is Compost? 
• Garbology Student Fact Sheet
• Wanted FBI- Garbology lesson.pdf
• “Who made this dirt” coloring page
• Other Garbology Worksheets

One Cool Earth's Zero Waste Videos:

http://www.onecoolearth.org/zero-waste.html

A few other great videos:

https://www.youtube.com/watch?v=dRXNo7Ieky8

https://www.youtube.com/watch?v=ufsbrz8IRgY

https://www.youtube.com/watch?v=V8miLevRI_o