Whole Earth Curriculum WEC

Lesson 07 — All Connected: When One Part Changes

Learners explain how living things in an ecosystem depend on one another and what happens when one part changes. A worked example traces a pond chain — water plants → small animals → fish and frogs → birds — and the ripple when the plants die. Learners then trace a change through a coral reef, mangrove, savanna, or forest, learning that a change ripples outward: change one part, and the rest feel it — and care and restoration can ripple helpfully too.

D10 P4: Contextual & Ecological Awareness D10.S3 55 minutes Draft

Objectives

Essential question

How do living things in an ecosystem depend on one another, and what happens when one part changes?

ecosystemdependripplechangebalance

Materials

Standard materials

Low-tech / no-cost

Enriched / lab & device

Works in different contexts

A ripple diagram about how living things depend on one another. Four boxes sit in a row connected by arrows: 'water plants,' 'small animals (snails, insects),' 'fish and frogs,' and 'birds.' Below, a dashed 'what if?' box reads 'if the water plants die: small animals lose food, then fish and frogs decline, then birds have less to eat.' A closing caption reads 'Every part depends on the parts around it. Change one, and the rest feel it.' Labels, arrows, and shapes, not color alone, carry the meaning so it prints clearly in grayscale.
A ripple diagram about how living things depend on one another. Four boxes sit in a row connected by arrows: 'water plants,' 'small animals (snails, insects),' 'fish and frogs,' and 'birds.' Below, a dashed 'what if?' box reads 'if the water plants die: small animals lose food, then fish and frogs decline, then birds have less to eat.' A closing caption reads 'Every part depends on the parts around it. Change one, and the rest feel it.' Labels, arrows, and shapes, not color alone, carry the meaning so it prints clearly in grayscale.

Lesson 7 — All Connected: When One Part Changes

Summary

Learners explain how living things in an ecosystem depend on one another and what happens when one part changes. A worked example traces a pond chain — water plants → small animals → fish and frogs → birds — and the ripple when the plants die. Learners then trace a change through a coral reef, mangrove, savanna, or forest, learning that a change ripples outward: change one part, and the rest feel it — and care and restoration can ripple helpfully too.

Objectives

  • Explain how living things in an ecosystem depend on one another and what can happen when one part changes. (D10.S3.05.02)

Connection

Pull one thread in a woven cloth and the whole cloth can pucker. An ecosystem is like that cloth. In a pond, the plants feed the snails, the snails and insects feed the fish, the fish feed the frogs and birds — each thread holds the next. When one thread is pulled hard enough, the rest feel it. Today you learn to trace that ripple, and to see that care can ripple the other way too.

Materials

  • Ripple-chain poster
  • Ecosystem ripple cards
  • Ripple page
  • Pencils

Preparation

  • Print or draw the ripple-chain poster.
  • Copy ecosystem ripple cards for each pair and a ripple page for each learner.
  • If using the string activity, have one length of string or yarn ready.

Facilitator note

This lesson is written to the learner (“you”). The skill to land is the ripple trace: name the chain of dependence, then follow one change through it (“if ___ changes, then ___, then ___”). Model the pond chain fully as a worked example. This builds on Grade 4 (producers, consumers, decomposers) and on this unit’s food-web and cycle work. Keep it hopeful and agency-focused: interdependence means harm can ripple, and so can care and restoration — never teach a “doomed ecosystem” without also teaching what can help. Distinguish evidence from values: how living things depend on one another is observable science; that we should care for ecosystems is a value this curriculum holds. See docs/facilitation.md and docs/philosophy.md §4–5.

Procedure

  1. Gather (5 min). Recall the food web you built earlier this year: energy flows from what is eaten to what eats it. Today, a bigger idea — what happens when one part of that web changes.
  2. Meet the pond ripple (12 min). Look at the poster. The water plants feed the small animals (snails, insects); the small animals feed the fish and frogs; the fish and frogs feed the birds. Now ask what if: if the water plants die, the small animals lose food, then the fish and frogs decline, then the birds have less to eat. One change — and the whole chain feels it. That is a ripple.
  3. Trace your own ripple (18 min). Choose an ecosystem card — a coral reef (if the coral bleaches, the fish that live in it decline, then the bigger fish and the fishers who depend on them feel it), a mangrove (if the mangroves are cut, young fish lose their nursery, then the larger fish and the birds decline, and the coast loses its storm shield), a savanna (if too many grazers are removed, the grass thickens, then fires and insects change, then other animals shift), or a forest (if the big trees fall, the shade and homes for many animals vanish, then the small animals and birds decline). On your ripple page, trace the chain and the change.
  4. Check with a partner (10 min). Say your ripple in one breath: “if ___ changes, then ___, then ___.” Then ask together: what could help it recover — what care would ripple the good way?
  5. Close (5 min). Living things hold each other up. Change one, and the rest feel it — and that means your care can ripple too.

Differentiation

  • Support: Provide a ripple page with the first two boxes filled in, and a sentence starter; work one chain aloud first.
  • Extension: Trace a change that helps (a plant restored, a predator returned) as well as one that harms, and compare how the two ripples differ.

Assessment

  • Formative (observation): Can the learner name a chain of dependence and trace one change through it, stating at least two “then” steps?
  • Peer check: Partners ask each other, “Did you trace the change all the way through — and did you name something that could help?”

Home connection

Pick a small ecosystem near home — a garden, a patch of grass, a pond, a tree. Name who depends on whom, and ask what would happen if one part changed.

Resources

  • Interdependence in ecosystems and the ripple effects of changing one part are core ecology content for this band (documented in children’s science references such as BBC Bitesize, National Geographic Kids, and Britannica Kids). Coral bleaching, mangrove nurseries, and forest habitats are described by NOAA, UNESCO, and the World Wildlife Fund in age-appropriate terms. The stewardship-and-hope framing follows docs/facilitation.md and docs/philosophy.md §12.