ScienceEcosystems & HabitatsAges 12–13

Toxins Building Up in Food Chains

Explain how organisms affect and are affected by their environment, including the bioaccumulation of toxic materials (e.g. pesticides, heavy metals) through food chains

Lesson

Set out your lesson

Practise the bounded task in Toxins Building Up in Food Chains; see exact limits before inferring broader coverage.

Before teaching

Use this short check, then start teaching.

Activity

Can distinguish concentration from total amount; no handling pollutants or advice about eating fish.

Policy

Exact directed source edges retained; earlier authorship is not learner attainment.

Printer, credit, and teaching notes

Exact directed source edges retained; earlier authorship is not learner attainment.

Materials

These supplied stage cards
Scrap paper and pencil; oral/pointing response where appropriate

Sequence

Read readiness and decide on support without treating prerequisite authoring as learner readiness.
Open Show first and explain its model.
Use Guided Try with support and its separate adult key.
Close Show and guided keys before Try, unless this Try is explicitly supported.
Reflect on an actual attempt, including help used.

No Printer

Use the supplied screen cards; copying the exact task to paper is optional, not required.

Privacy

Use only invented scenarios and optional anonymous local notes. Do not request names, photos, family finances, medical data, accounts or uploads. Stop uncomfortable physical activity.

Use the complete materials on screen or print only the current sheet. Keep adult guidance out of learner view.

Next: Show

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Entire curriculum

1858 concepts · 9 subjects

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Teaching approaches

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1 approach

Selected Default Gakuva

Practise the bounded task in Toxins Building Up in Food Chains; see exact limits before inferring broader coverage.

Family records and proof options

Keep a record of your learning

Save photos, notes, and attendance. Export a proof packet for compliance or portfolio reviews.

View learner plans ($12/mo per learner) See sample family archive

Learning resources

Extra practice links — they do not replace Gakuva’s teaching approach.

NASA Climate Kids · Practice link — not the full lesson

Plants and Animals

Open practice(new tab)

Before you open · source notes

Plants and Animals supports Toxins Building Up in Food Chains. An adult previews and guides; this is a learning page, not a scored quiz.

Free educational page, no sign-in required for the tested path.

Before you open

Ask the learner one fact they learned and one question they still have.

Opening this link does not save learning or assess mastery.

Source, access and review notes

Public NASA Climate Kids page. An anonymous GET on 2026-11-12 returned HTTP 200 with no login or payment prompt for this URL. Opening the link does not save practice or assess mastery. An adult should preview and guide the learner.

NASA Climate Kids. “Plants and Animals.” External page; Gakuva does not copy, host, embed, or redistribute materials.

Unknown — link only

Check understanding

Defines bioaccumulation and explains why toxins increase in concentration higher up the food chain
Gives a real example of bioaccumulation (e.g. DDT in peregrine falcons, mercury in tuna)
Explains how organisms can change their habitat (e.g. earthworms aerating soil, beavers creating wetlands)
Discusses why top predators are most at risk from bioaccumulation

“If your child heard that large fish like tuna can contain more mercury than small fish, could they explain why that is — even though the tuna didn’t encounter mercury directly?”

Curriculum record

Type: Conceptual
Subject: Science
Domain: Ecosystems & Habitats
Age range: Ages 12–13

Standards

ngss-ms:MS-LS2-4ngss-ms:MS-LS2-5uk-nc-2013:KS3.Sci.Bio.Ecosystem.3