Students will observe decomposition in a pile of grass clippings and in a compost heap over time.
A lesson plan for grade 5 Science
- Investigate ways to prevent or reduce pollution and the misuse of natural resources.
- Participate in a project, which includes recycling and reduction.
Time required for lesson
- grass clippings, enough to make a cubic meter pile
- meter stick with a thermometer attached
For each group:
- a five-gallon bucket with holes drilled all around the side and bottom
- one or two gallons of rich garden soil
- objects to put in the compost heap: aluminum can, plastic, shredded newspaper, lettuce, orange peels, leaves, twigs, etc
- plastic sheet for spreading out compost during observations
You may wish to have your students bring things to school to put in the compost heap.
- Make a cubic meter pile of grass clippings. Start a record of the internal temperature, appearance, volume, and smell of the pile. Record observations of the pile when it is first set up and again several times over the next three days. Be sure to lift several layers of clippings to observe the center of the pile each time. Discuss and record the changes observed.
- Put the soil in the bucket. List and then bury the materials in the soil. Predict which object will decompose fastest and which will decompose the slowest. Have students categorize the contents by renewable/nonrenewable, recyclable/non-recyclable, biodegradable/non-biodegradable.
- One week later, spill out the compost on the plastic sheet. Refer to the original list and record any changes observed. Allow students to modify their charts and allow further predictions. Students should continue to record internal temperature, appearance, volume, and smell of the pile.
- Spill out and observe the objects again one month later. Record data. Have students create charts and graphs to demonstrate the changes in temperature and volume. Students should classify compost contents into categories, renewable/nonrenewable, recyclable/non-recyclable, and biodegradable/non-biodegradable. Students will also write a descriptive essay on the changes they observed, and a persuasive essay encouraging others to recycle. Extension: Invite others classes to a recycling program created by your class.
- Continue to make regular observations as long as possible. Water the compost heap each week to keep it moist.
Teacher will assess objectives through students’:
- observations in their science log
- recorded data
- charts and graphs of temperature and volume of compost heap
- descriptive essays
- persuasive essays
- participation in recycling program
North Carolina curriculum alignment
- Goal 1: The learner will conduct investigations to build an understanding of the interdependence of plants and animals.
- North Carolina Essential Standards
- Science (2010)
- 5.L.2 Understand the interdependence of plants and animals with their ecosystem. 5.L.2.1 Compare the characteristics of several common ecosystems, including estuaries and salt marshes, oceans, lakes and ponds, forests, and grasslands). 5.L.2.2 Classify the...
- Science (2010)