Animal Groups and Their Features — Answers
Answer sheet with model answers and success criteria for the 3rd Grade living things & life cycles worksheet.
Success TutoringWorksheetsAnswer sheet3rd Grade · Science · Living Things & Life CyclesAnimal Groups and Their Features — Answers
Part A: Sorting animals into groups
Read the passage. Then circle the best answer.
Scientists sort animals into groups by looking at their features (what their bodies are like and how they live).
Animals with a backbone (vertebrates) include: Mammals — have hair or fur and feed their young on milk; most give birth to live young. Birds — have feathers, a beak and two wings, and lay eggs with hard shells. Fish — live in water, breathe with gills and have fins; most have scales. Reptiles — have dry, scaly skin; most lay eggs. Amphibians — have moist skin and usually begin life in water.
Animals without a backbone (invertebrates) include insects. Adult insects have six legs and three body parts (head, thorax and abdomen). Spiders and worms are invertebrates too, but they are not insects.
Some animals are tricky! A bat can fly, but it has fur and feeds its young on milk, so it is a mammal. A penguin cannot fly, but it has feathers, so it is a bird.
- Afeathers
- Bfur
- Cgills
- Dsix legs
Answer: feathers
Every bird has feathers. No other animal group has feathers.
- Afish
- Bmammals
- Camphibians
- Dreptiles
Answer: mammals
Whales breathe air with lungs and feed their babies milk, so they are mammals, not fish.
- Afour
- Beight
- Csix
- Dten
Answer: six
All adult insects have six legs and three body parts.
- Areptiles
- Bfish
- Cbirds
- Damphibians
Answer: amphibians
Amphibians, like frogs, usually begin life in water and have moist skin.
- Aa lizard
- Ba frog
- Ca salmon
- Da bat
Answer: a lizard
Lizards have dry, scaly skin. They are reptiles. A frog is an amphibian, a salmon is a fish and a bat is a mammal.
- AIt can bite.
- BIt has eight legs.
- CIt is very small.
- DIt lives in a web.
Answer: It has eight legs.
Insects have six legs. Spiders have eight legs and two body parts.
Part B: Features of each group
- birds
- mammals
- insects
- feathers
- six legs and three body parts
- feed their young on milk
Answer: birds → feathers; mammals → feed their young on milk; insects → six legs and three body parts
Answer: gills
Answer: vertebrate
Answer: It has fur, not feathers, and it feeds its young on milk.
Part C: True or false?
Write True or False.
Answer: False
Bats and many insects can fly, but they are not birds. Birds are the animals with feathers.
Answer: True
Penguins cannot fly, but they have feathers and lay eggs with hard shells, so they are birds.
Answer: False
A shark breathes with gills and has fins. It is a fish.
Answer: True
Snakes have dry, scaly skin. They are reptiles.
Part D: Working scientifically: a mini-animal hunt
Record what you see. Draw one animal and label its features.
With a grown-up, look for small animals in a garden or a park, or under fallen leaves. Look closely (a magnifying glass helps) but do not touch or pick them up. Put back anything you move.
Answer: Any animal, e.g. an ant, a beetle, a spider, a snail, a worm or a bird.
Answer: The number observed, e.g. ant 6, spider 8, snail 0, worm 0, bird 2.
Answer: Insect if it has six legs and three body parts (e.g. an ant); not an insect if not (e.g. a spider has eight legs).
Model answer: An ant is an insect. It has six legs and its body has three parts: a head, a thorax and an abdomen.
Success criteria:
- Names an animal and a correct group
- Gives two features that belong to that group
- Uses observations, not just guesses
Marking tips
- Give credit for correct method even when the final answer slips — the working shows where the thinking went right.
- For open-ended tasks, use the success criteria as a checklist rather than looking for one "right" answer.
- Celebrate what went well first, then pick one thing to work on next.
Great work. Here's what to try next: