ScienceForces & MotionAges 12–13

Newton's Third Law

State and apply Newton's Third Law: every force has an equal and opposite reaction force acting on a different object, distinguishing action-reaction pairs from balanced forces

Lesson

Set out your lesson

Practise the bounded task in Newton's Third Law; see exact limits before inferring broader coverage.

Before teaching

Use this short check, then start teaching.

Activity

Can name both objects in an interaction; all examples are descriptions, no pushing people, rockets or weapons.

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

Adult extras

Teaching limits and safe use

These are finite task opportunities, not proof of mastery. Record what was attempted and what support was used.

Conceptual interaction pairs; no physical force measurements. Exact firearm-recoil clause is blocked and replaced with a harmless magnet example, not claimed equivalent full coverage.

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.

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Teaching approaches

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1 approach

Selected Default Gakuva

Practise the bounded task in Newton's Third Law; 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.

PhET Interactive Simulations · Practice link — not the full lesson

Forces and Motion: Basics

Open practice(new tab)

Before you open · source notes

Forces and Motion: Basics supports hands-on exploration for Newton's Third Law. Not every lab worksheet.

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

Before you open

Ask the learner what they changed in the sim or page and what they observed.

Opening this link does not save learning or assess mastery.

Source, access and review notes

Public PhET Interactive Simulations 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.

PhET Interactive Simulations. “Forces and Motion: Basics.” External page; Gakuva does not copy, host, embed, or redistribute materials.

Unknown — link only

Check understanding

States Newton's Third Law correctly, identifying both the action and reaction force and the objects they act on
Gives at least two real-world examples (e.g. rocket propulsion, swimmer pushing off a wall)
Distinguishes a Newton's Third Law pair from balanced forces on the same object
Explains why a gun recoils when fired using Newton's Third Law

“If your child saw a video of a rocket launching into space, could they explain what force is pushing the rocket upward and where that force comes from — and which law of motion that demonstrates?”

Curriculum record

Type: Conceptual
Subject: Science
Domain: Forces & Motion
Age range: Ages 12–13

Standards

ngss-ms:MS-PS2-1uk-nc-2013:KS3.Sci.Phys.MotionAndForces.7