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GROW · SCIENCE · Lesson 10 of 11

Four cases, one comparison challenge

Learning intention

Compare named animal life cycles using similarities, differences and a valid counterexample.

All four animals lay eggs.

Does that make all four birds?

Your job is to test the claim with evidence.

Success looks like

  • Compare two species using the same feature.
  • Use a life-cycle stage as evidence for a difference.
  • Explain why one shared feature does not make two animals the same group.
Retrieval

GROW · SCIENCE · Lesson 10 of 11

Use the stage words carefully

R1. What does an adult animal become able to do?

R2. Name an animal with a larva stage.

R3. Does one individual turn back into an egg?

I do

GROW · SCIENCE · Lesson 10 of 11

I choose a feature, then compare

I follow the common-frog stages.

A tadpole and adult differ in body form.

I look for a pupa; none is present.

Common frog: major changes in body formClockwise sequence: Eggs in pond; Tadpole larva; Froglet four legs; tail shrinking; Adult frog can reproduce. Adults produce the next generation of eggs.Common frog: major changes in body formEggs in pondTadpolelarvaFrogletfour legs;tail shrinkingAdult frogcan reproduceAdults produce the next generation of eggs.
Common frog: major changes in body form
Diagram description

Clockwise sequence: Eggs in pond; Tadpole
larva; Froglet
four legs;
tail shrinking; Adult frog
can reproduce. Adults produce the next generation of eggs.

I do

GROW · SCIENCE · Lesson 10 of 11

I use the same feature for the monarch

Both routes include eggs and a larva.

Only this monarch route has a pupa.

A shared stage does not make the whole cycle identical.

Monarch: a different developmental routeClockwise sequence: Egg on milkweed; Caterpillar larva; Chrysalis pupa; Adult monarch can reproduce. A pupa is present here; it is not a stage in every insect.Monarch: a different developmental routeEgg on milkweedCaterpillarlarvaChrysalispupaAdult monarchcan reproduceA pupa is present here; it is not a stage in every insect.
Monarch: a different developmental route
Diagram description

Clockwise sequence: Egg on milkweed; Caterpillar
larva; Chrysalis
pupa; Adult monarch
can reproduce. A pupa is present here; it is not a stage in every insect.

Continue within this stage’s shared time.

I do

GROW · SCIENCE · Lesson 10 of 11

I test an “all” claim

Platypus and robin both lay eggs.

Platypus young receive milk; robin chicks do not.

The platypus disproves “all egg-layers are birds”.

Eggs do not mean the same animal groupParallel comparisons of platypus and robin: both lay eggs, but platypus young receive milk and robin chicks receive food from parents. No arrow connects the animal groups.Compare one feature at a timePlatypus: mammalRobin: birdEggs in a burrowYoung receive milkEggs in a nestChicks receive foodSame egg-laying feature; different animal groups.
Eggs do not mean the same animal group
Diagram description

Parallel comparisons of platypus and robin: both lay eggs, but platypus young receive milk and robin chicks receive food from parents. No arrow connects the animal groups.

Continue within this stage’s shared time.

We do

GROW · SCIENCE · Lesson 10 of 11

Comparison bureau: shared-feature sort

Go to interactive investigation

Use cards F, M, P and R.

W1. Group them by one feature, then regroup.

Explain why the groups changed.

FeatureQuestion to use
Egg locationWhere are eggs laid?
PupaIs this stage in the route?
Milk feedingDo young receive milk?

Comparison bureau: change the sorting rule

Predict first, test the model, then explain using the evidence. Move at your own pace; paper W1–W3 tasks assess the same reasoning.

Decision 1 of 3

Common frog and monarch both have which stage?

Choose, test, then explain together. Evidence diagrams appear only after your test. Diagram transitions explain the model; they do not represent real elapsed time. Use Pause model to stop transitions and model controls, or your device’s reduced-motion setting. The printed We do activity provides the paper route.

We do

GROW · SCIENCE · Lesson 10 of 11

Build a precise comparison

W2. Compare common frog with monarch.

Give one similarity and one difference.

Use “both”, “whereas” or a labelled pair.

Continue within this stage’s shared time.

We do

GROW · SCIENCE · Lesson 10 of 11

The claim challenge

W3. “All egg-layers are birds.”

Select a counterexample and explain it.

Can four species describe every animal?

Continue within this stage’s shared time.

Hinge

GROW · SCIENCE · Lesson 10 of 11

Which comparison uses evidence fairly?

Choose the statement that the cards support.

You do

GROW · SCIENCE · Lesson 10 of 11

Your independent investigation

Choose one response route.

Build an evidence-based comparison.

Test one broad claim with a named case.

You do

GROW · SCIENCE · Lesson 10 of 11

Use the evidence

Use the same feature for both animals.

Name your species and evidence card.

Distinguish “these examples” from “all animals”.

Continue within this stage’s shared time.

You do

GROW · SCIENCE · Lesson 10 of 11

Check before sharing

Does my explanation answer the question?

Have I named the evidence or process?

Have I kept the conclusion within its limits?

Continue within this stage’s shared time.

Review

GROW · SCIENCE · Lesson 10 of 11

Compare and improve

Show a precise similarity or difference.

Check the named evidence.

Improve one broad or vague statement.

Review

GROW · SCIENCE · Lesson 10 of 11

A question worth investigating

Suggest one next question about this lesson’s evidence.

Choose a question whose answer would improve our model.

Continue within this stage’s shared time.

Exit

GROW · SCIENCE · Lesson 10 of 11

Show the science you can explain

E1. Give a frog–monarch similarity.

E2. Give one difference in stages.

E3. Explain a counterexample to “all egg-layers are birds”.

My science task sheets

Choose one route with your teacher. Shared evidence and the exit sheet appear in every route. Your work stays here while the page is open; save it before closing.

1 • Shared evidence: comparison bureau

Named-species summaries. Use these cards for W1–W3 and your selected route.

F • Common frog

Eggs are laid in pond water. Tadpoles are larvae with tails; they develop into froglets and then adults. No pupa stage. No milk feeding.

M • Monarch butterfly

Eggs are laid on milkweed. Caterpillars are larvae; they become pupae, then adult butterflies. No milk feeding.

P • Platypus

A mammal that lays eggs in a burrow. The young hatch and receive milk from their mother; they grow to reproductive maturity. No pupa.

R • Robin

A bird that lays eggs in a nest. Chicks hatch, grow feathers and become fledglings, then reproductive adults. Parents bring food; no milk feeding.

Comparison rule

Use the same feature on both sides: egg location, pupa stage, or milk feeding. A blank in our evidence means not supplied, not automatically absent.

Cycle rule

Adults produce offspring. The next eggs belong to a new generation; the same individual does not turn back into an egg.

2 • Supported route: compare a pair

Use cards F and M. Word bank: eggs / larva / pupa / adult.

S1. Which stage occurs in both routes?
S4. A platypus lays eggs. Is it a bird?

3 • Standard route: feature table

Use the same question for each animal.

SpeciesPupa present?Young receive milk?
Common frog
Monarch
Platypus
Robin

4 • Stretch route: challenge the rules

A strong claim stays within the evidence.

5 • Exit and reflection

Answer independently using scientific features.

Slide 1

TA Brief

Current stage

Objective

Compare named animal life cycles using similarities, differences and a valid counterexample.

Preparation

Method precautions

Practical alternative

All evidence needed is on paper or screen; sort or annotate cards at a desk.

Access and regulation

Supported: Compare two named species with a feature word bank.

Standard: Complete a feature table and justify one similarity and two differences.

Stretch: Test broad classification claims and state the limits of the sample.

Regulation: Offer private writing, pointing, drawing or adult scribing. Allow pass-and-return for public questions and desk-based participation. Choose support from current learning evidence, not fixed ability labels.

Teacher answers

R1–R3

Reproduce; a named animal with a larva such as frog or monarch; no, the next generation contains new individuals.

W1–W3

W1 pupa: monarch yes, other three no; milk: platypus yes, other three no. Groups change because the feature changes. W2 both eggs/larvae; monarch has pupa and frog does not. W3 frog, monarch or platypus is a non-bird egg-layer; platypus is a mammal.

Hinge A–C

A false: same feature is not identical cycle. B correct. C false: platypus is an egg-laying mammal.

S1–S5

S1 egg. S2 larva; pupa. S3 egg→caterpillar→pupa→adult. S4 no, mammal. S5 name a non-bird egg-layer and state that this contradicts all egg-layers being birds.

N1–N4

N1 frog no/no; monarch yes/no; platypus no/yes; robin no/no. N2 both eggs or larvae, but pupa only monarch. N3 both lay eggs; platypus young receive milk whereas robin chicks receive other food from parents. N4 valid counterexample; a sample of four cannot establish every possible animal life cycle.

T1–T4

T1 three accurately matched features, for example frog and monarch: egg location pond versus milkweed, larvae both, pupa absent versus present. T2 false: tadpoles are larvae but no pupa follows. T3 false: platypus lays eggs and feeds young milk. T4 missing information is not evidence of absence; record not supplied/unknown and seek a reliable source.

E1–E4 / assessment

E1 eggs or larvae. E2 pupa only monarch. E3 named correct non-bird case and contradiction. E4 adults produce new offspring, not themselves becoming eggs. Secure: matched comparison and valid counterexample; re-teach vague differences by selecting one common feature question. Reflection accepts a relevant evidence question.

Sources checked for this lesson

Word help

compare
Describe similarities and differences using the same feature.
larva
An immature stage with a different body form from the adult.
pupa
A developmental stage between larva and adult in insects with complete metamorphosis.
mammal
An animal in the group whose females produce milk for young.
counterexample
A case that shows an all-or-never claim is false.

Cold Call

Give thinking time. Invite a response by voice, pointing or showing work. A pupil can pass; check in privately when useful.

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Take a quiet pause.

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