Preview · the opening missionRead this to the class:
Every autumn, trees drop tonnes of leaves. Every year, animals and plants die in the forest. And yet the forest floor isn't buried kilometres deep in dead stuff. Someone, or something, is cleaning up. Your team's job: catch the cleanup crew at work.
Teams of three, with three jobs that rotate: Lead (handles the materials), Timer (keeps each step moving and checks the seals), Recorder (writes and draws).
Look inside the PDF
Sample pages, stamped “preview”. The download is the clean, full lesson.
In the full lesson PDF
- Predict (5–10 min)
- Hunt (20 min)
- Reveal (10–15 min)
- Act (10 min)
- Background for the teacher
- Assessment
- Student sheet
On the student sheet
- My prediction
- Mould bag log
- Leaf bags
- Thank-you to the cleanup crew
- Exit ticket
US Letter, prints cleanly in black and white. The student sheet is on its own page, ready to photocopy.
Free with an account (any 3 lessons), or US$19 / C$25 for all 4 lessons in this unit.
What students show by the end
- Records observations
- Explains decomposers
- Claim, evidence, reasoning
From the lesson’s rubric, which scores each one as not yet, getting there or got it.
Questions teachers ask
How long does “Who cleans up?” take?
45 min to set up, 5 min check-ins twice a week, then 30 min after 2 weeks (bread) and 20 min after 4 to 6 weeks (leaves). Group size: teams of 3.
How much prep does it need?
20 minutes: collect a grocery bag of dry fallen leaves (or ask students to bring some). Fill one tub with moist garden soil or potting mix with some garden soil mixed in. Cut mesh or tulle into squares about 25 cm (10 in) across. Check your class list for mould allergies and asthma before the lesson.
What materials do I need?
Bread from a bakery or homemade (grocery bread with preservatives moulds slowly); soft fruit; heavy zip-top freezer bags, about 1 L (1 qt); clear packing tape and a permanent marker; dry fallen leaves; mesh, tulle or netting squares, about 25 cm (10 in), and twist ties; and 3 more. Cost: about $25 for a class of 30.
Which curriculum standards does it cover?
NGSS (US): 5-LS2-1. It also matches Cambridge Primary Science, Stages 4 and 6 (not endorsed by Cambridge).
What’s in the lesson PDF?
A teacher guide that walks you through predict, hunt, reveal, act, background for the teacher and assessment, then a student sheet (“My prediction”, “Mould bag log”, “Leaf bags”, “Thank-you to the cleanup crew” and “Exit ticket”) on its own page, ready to photocopy. It’s US Letter and prints cleanly in black and white.
Can I try it for free?
Yes. A free account includes any 3 full lessons of your choice, and this can be one of them. After that, this unit is US$19 (C$25) for all 4 lessons, yours to keep, or every lesson is US$79 (C$109) a year.