COMPOSTING  APPLIED

Developed by: Harold Leate 

Summary: Students will learn about recycling as a way of reducing our growing waste management problem and how to conserve our natural resources. 

Connection to Curriculum: As the students learn about Geology and food webs; the importance of conserving our natural resources will be an important aspect of this curriculum. The students will conduct a practical exercise in composting to demonstrate a simple method of conserving natural resources. The students can also investigate composting as a way of reclaiming some of the once fertile land that has been over used and now lays in waste. 

Time: This project will take one class period to initiate the project (start the compost bins). Then a simple monitoring program to insure that the compost bins are kept alive. In the spring time two class periods will be utilized to apply the compost material to the test site. Extension: apply a manufactured fertilizer to another patch of grass and compare effectiveness and cost. 

Materials:             

•                          10 Gallon opaque plastic container w/lid
  1 Meter square piece of window screen
  1 ea Misting bottle (to keep compost moist)
  1 liter soil (starter material)
  250 ml oatmeal (starter material)
  1 liter shredded paper (moistened) (starter material)
  250 ml table scraps (no meat products) (starter material)
  500 grams worms 

Objectives: 

TAAS Objective 1 The student will demonstrate the ability to conduct scientific inquiry, draw inferences from data, and communicating results.

• demonstrate safe practices during field and laboratory investigations.

• make wise choices in the use and conservation of resources and the disposal or recycling of materials.

• collect data by observing and measuring

•   communicate valid conclusions

• construct graphs, tables, maps, and charts to organize, examine, and evaluate data.

TAAS Objective 3 The student will demonstrate an understanding of the interdependency among living systems and the mechanisms of genetic change. 

• describe interactions within ecosystems

•   identify that change in environmental conditions can effect the survival of individuals and of species.

TAAS Objective 5  The student will demonstrate an understanding of the cycles that exist in Earth systems and how those systems are affected by natural events and human activities.

• describe how human activities have modified soil, water, and air quality.

Procedures:  

1. First step is to prepare the compost bin for the worms, this should be done in the fall shortly after school begins. To insure that the worms get plenty of oxygen you need to cut a 15 cm X 23 cm hole in the lid of the plastic container. Take a piece of window screen 18 cm X 26 cm and attach it to the inside of the container lid so that it covers the hole. The screen may be attached with duct tape or any other wide tape. 

2. Combine the starter materials in the plastic container. Be sure to moisten the paper prior to adding it to the starter mix. To moisten the paper you take a hand full and dip it into a container of water or run water over the paper. Allow the excess water to drain off the paper before adding it to the starter mix. 

3. Sprinkle 500 grams of worms over the compost starter mix. Place the lid on the plastic container and place the container in a dark place. If the container is left out in the light the worms will go to the bottom and not eat the food on top. Students should check the container every couple of days. As the food in the compost bin is consumed more may be added. As a good gauge; 500 grams of worm can usually consume 500 grams of waste material in a week, as your worm population increases you may want to divide the worms and start a second compost bin. Many types of material may be put into the compost bin but never put any meat products into to the compost bin. When the students check the compost bin they should use the spray bottle to moisten the material in the bin. Over moistening or over feeding the worms will result in the growth of mold and fungus which will result in a bad odor. Student should stir the compost bin about every second or third week, be sure that students wear the proper safety equipment when performing this task.  

4. To remove some of the compost material you should take the container out of the dark and remove the lid so that the compost material is exposed to the light. After a couple of hours the worms will have moved to the bottom away from the light and you will be able to scrape the finished material off the top and transfer it to another container or to a test site. After completing this task be sure to replace the compost bin back into the dark location again.  

5. The composted material should be applied to a test location. Be sure to discuss with the student the use of a control site and variables. Students should observe and collect data from the test site. The students should combine this data with the data that they have collected from the production of compost material. They should analyze the data and answer the below questions. 

Questions:  

1. How do we benefit from the worms that live in our soil ? 

2. Compare and contrast the usefulness of compost material and manufactured fertilizers. 

3. Did you find the development of any other organisms in your compost bin ? What kind were they ? 

4. How did you use your composted material, and how effective was its use ? 

5. Compare and evaluate the cost effectiveness of composting over the use of manufactured fertilizers ? 

6. What role do worms play in the food chain ? 

Evaluation: The students will work in cooperative groups. The group will select one of the questions and using the scientific method develop an experiment that will provide the solution to the question. The experiment will be evaluated using the attached rubric. 

Expanding the Lesson:  

1. The students may study the use of a large scale composting center as a way of help to reduce the solid waste material that goes into our sanitary land fills. 

2. The students can conduct research to see if there are any recycling facilities that produce compost and what is the effectiveness of the program ? What is the expense of operating such a facility. 

Resources: 

A Green Guide to Yard Care. Texas: Texas Natural Resource Conservation Commission 

Environmental Teaching Guide, Vol 2. Texas Natural Resource Conservation Commission