Composting Food Scraps

3.1 based on 22 ratings

Updated on Nov 06, 2014


Earth Science


4th - 8th grade

Difficulty of Project



$15 per student

Safety Issues


Material Availability

Easy; materials can be easily obtained

Approximate Time Required to Complete the Project (Including analysis and write-up)

3 months

What is the project about?

The composting project is designed to teach students how food scraps can be composted. It also teaches students how to put their composted materials to good use.

What are the goals?

The goals of the composting project are to teach students how to compost and how composted materials enhance plant growth. The project also teaches students about waste management and recycling.

What materials are required?
  • Plastic bin (1 will be used for the entire class)
  • Soil (for part 1, 2 shovels worth is needed; for part 2, 1 1/2 planting pots worth is needed)
  • Saw dust (2 shovels worth)
  • Leaves, grass clippings, weeds (2 shovels worth)
  • Food scraps (vegetables, fruits, coffee grounds) (2 shovels worth)
  • Water
  • Newspaper (2 shovels worth of shredded paper)
  • Planting pots (3 per student)
  • Lettuce seeds (handful per student)
Where can the materials be found?
Most materials can be found at a plant nursery or all-purpose store (such as Target)

  • What materials can you compost?
  • Why is composting good for the environment?
  • What is compost?
  • What effect does compost have on plants?

An understanding of the process of composting is essential. The terms biodegradable and mulch should be reviewed.

This project has 2 parts:
  • Part 1: Create your own compost
  • Part 2: Test compost effect on plants
Part 1: Create your own compost
  1. Set up your composting bin (a large plastic storage bin or a plastic garbage bin will work)
  2. Place bin in an accessible outdoor area with plenty of space around it. The locations should have a water source nearby.
  3. Put old plant leaves, grass clippings/weeds, fruit/vegetable food scraps, coffee grounds, etc. into the bin.
  4. Sprinkle the mix with water. The mix should be moist, but not overflowing with water.
  5. Add shredded newspaper and sawdust.
  6. Sprinkle the mix with water.
  7. Add soil.
  8. Sprinkle the mix with water.
  9. If desired, you may add earthworms to the compost after one week. This will speed up the composting process, but is not necessary.
  10. Sprinkle water on the compost mix every week and stir if desired (stirring not necessary).
  11. After 4-6 weeks, your mix should be a dark compost mix (it should look like soil).
Part 2: Test compost effect on plants
  1. Fill one plant pot with compost (leave one inch of space from the top of the pot).
  2. Label this pot 'Compost Only'.
  3. Plant 5 -10 seeds in this pot.
  4. Fill second plant pot with a mixture of 1/2 soil and 1/2 compost (leave one inch of space from the top of the pot).
  5. Label this pot ''Compost and Soil Mix'.
  6. Plant 5 -10 seeds in this pot.
  7. Fill the third plant pot with soil (leave one inch of space from the top of the pot).
  8. Label this pot "Soil Only"
  9. Plant 5 -10 seeds in this pot.
  10. Water all pots evenly and set in an area of partial to no sunlight.
  11. Monitor lettuce growth over several weeks and record any differences in physical characteristics of the plants (color, size, etc).
  12. When lettuce is full grown, pick and enjoy!

Brooke Greco graduated from UC Berkeley, and has volunteered her time with several after-school learning programs over the last several years. Brooke served as a Citizen's Schools Teacher in Redwood City, CA, where she taught a course on the rain forest. In addition, Brooke served as aÂteacher at the New Era Galapagos Foundation and taught English and conservation practices to local youth of the Galapagos Islands.

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