2026–27 · Backup lesson · Spring 2027
Use Decomposition Evidence in Compost Decisions
Adult extension of: What Is Decomposition?
Unscheduled alternative · available resource
Compare fresh plant material with documented decomposing samples and finished compost. Practice separating suitable compost inputs from unsuitable materials while distinguishing drying from actual biological breakdown.
Curriculum skill focus: Life cycles of matter, sequencing, observation, ecosystem awareness
01 · Learning
Objectives
- Describe visible changes without equating every brown leaf with decomposition.
- Explain a role for decomposers in recycling matter.
- Choose appropriate inputs for the local compost system.
02 · Preparation
Materials
Fresh permitted leaf; dry leaf in closed container; documented decomposing leaf photographs; finished compost in closed container; local compost acceptance guidance; large input cards; gloves and tongs if used; observation sheet.
03 · Practice
Adult project
- 1
Start with the local compost system’s accepted-material list and a practical question about garden cleanup. Choose to examine closed samples, pictures, or handled materials, and confirm that smell and touch are optional.
- 2
Compare a fresh leaf, a dry leaf, and dated images of decomposing material. Describe color, brittleness, fragmentation, and loss of recognizable structure, noting that drying alone does not prove decomposition.
- 3
Arrange documented photographs by their actual dates. Add cards for bacteria, fungi, and other decomposers, and explain that their activity changes dead material over time; do not infer a precise age from appearance alone.
- 4
Sort input cards according to the actual local compost guidance. Separate garden leaves or accepted plant scraps from plastic, treated wood, and locally excluded items, and identify any uncertain item for checking rather than guessing.
- 5
Choose one permitted input and plan how to add it responsibly, following the system’s balance and moisture guidance. If tracking a sample, use dated photographs or a managed ventilated compost setup rather than opening moldy jars in class.
- 6
Record one observed change and one practical sorting decision. Return closed samples, clean tools and hands, and set a realistic later observation date if a compost comparison will continue.
Evidence & interpretation
What the investigation shows
Decomposition involves biological and chemical breakdown of dead organic material and the recycling of nutrients. Drying and fragmentation can occur alongside it but are not alone proof of microbial decomposition; compost conditions and accepted inputs vary by system.
Practical connection
Why this work matters
Compost decisions help manage garden waste and return useful organic matter to planting systems.
Participation by choice
Individual access options
- Use photographs and closed finished-compost samples to avoid odor and direct contact.
- Sort large cards into two choices or compare more detailed system-specific rules at a self-chosen pace.
- Direct a partner, speak, point, or use AAC to make compost decisions; decline smell, touch, or an observation visit without penalty.
Review & transfer
Reflect on the work
- Which change did you observe, and which explanation came from background information?
- Which compost input would you check before adding it?