Science // Dinosaurs & Paleontology

Dinosaur Sizes

Compare dinosaur sizes to familiar things — some dinosaurs were as tall as a house, others were as small as a chicken — and understand that dinosaurs came in a huge range of sizes

Ages
5 to 7
Type
Concept
Builds on
1 topic
Leads to
1 topic

Quick check

Can the learner tell you that some dinosaurs were enormous and others were tiny — maybe using comparisons like 'as tall as a building' or 'as small as a cat'?

Ask this to see whether the topic is secure.

Topic // Mastery

What mastery looks like

What a learner can do once this topic is secure.
  • Compare the size of a large dinosaur to a familiar object like a bus or house
  • Name a very large dinosaur (e.g. Brachiosaurus) and a small one (e.g. Compsognathus)
  • Use words like 'taller than', 'longer than', 'heavier than' when comparing

Topic // Map

Where this fits

What to learn first and what this topic opens up, with the reason for each link. Required links come first.
  • RequiredMust come first
  • HelpfulHelps, but not essential

Before this

1 topic
  • Dinosaurs & Paleontology // Ages 5 to 7

    Must know some dinosaur species before comparing their sizes

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Dinosaur Sizes

Ages 5 to 7 // Concept

Leads to

1 topic
  • Dinosaurs & Paleontology // Ages 7 to 9

    Placing the Mesozoic periods in order and understanding that different dinosaurs lived in different periods is contextualised by the prior knowledge that dinosaurs varied enormously in size — size variation across time periods supports the concept of evolutionary change

Topic // Research-informed

Teaching notes

From the Marble Skill Taxonomy. These notes have not been validated in classrooms, so treat them as a starting point for your own judgement.

The approach

For ages 5–7, teach that dinosaurs came in a huge RANGE of sizes — some as tall as a house or long as a bus, others as small as a chicken — by comparing dinosaurs to familiar referents (a child, a bus, a house, a chicken) using comparative language (taller than, longer than, heavier than, smaller than). The central insight is the range itself, not absolute metres or tonnes, so always pair a giant with a tiny dinosaur. Keep comparisons at a shared scale so they are fair.

Common misconceptions

  • 'All dinosaurs were enormous' — many were small; some were chicken- or turkey-sized.
  • 'The scariest/meat-eaters were the biggest' — the very largest were plant-eating long-necks; some carnivores were tiny.
  • 'Dinosaurs were all bigger than any animal today' — small dinosaurs were the size of familiar small animals.
  • 'Bigger dinosaur means it lived more recently / is more advanced' — size is not a timeline.
  • 'Pictures show real relative size' when objects aren't drawn to a common scale — fair comparison needs the same scale.

Useful representations

  • Silhouette scale line-ups: dinosaur beside a person, bus, house, and chicken.
  • An order-by-size strip from smallest (chicken-sized) to largest (long-neck giant).
  • A 'stand next to it' overlay putting a child figure beside each dinosaur.
  • Comparative-word cards (taller/longer/heavier) attached to each comparison.

Teaching practices

  • Always compare to a FAMILIAR referent (child, bus, house, chicken) rather than abstract units — body/object scale is how young children grasp size.
  • Deliberately include a tiny dinosaur next to a giant so the RANGE (not just bigness) is the takeaway.
  • Use rich comparative language consistently: taller than / longer than / heavier than / smaller than.
  • Let children physically or visually line up figures to order them, making comparison an action.
  • Relate to their own height ('this one's leg is taller than your whole class standing on each other') to make scale visceral.

Activities to try

  1. 1

    Compare dinosaurs to your own world (scale stage)

    Why it works: Dinosaurs ranged from chicken-sized to house-sized; not all were huge. Size is a relation you understand by comparing to familiar things at the same scale.

    1. Place a chosen familiar object on a comparison stage: yourself (a child figure), a bus, a house, and a chicken.
    2. Bring a dinosaur alongside the chosen object at the same shared scale and look at how they compare — e.g. Brachiosaurus reaching past the roof of a house, Compsognathus barely bigger than the chicken.
    3. Say or complete a comparison out loud: 'Brachiosaurus is taller than the house', 'Compsognathus is smaller than a big dog'.
    4. Use a 'stand next to it' option to drop a small version of yourself beside each dinosaur and say how it compares to you ('its leg is taller than me!').
    5. Deliberately compare a giant and a tiny dinosaur one after the other so you feel the contrast.
  2. 2

    Order dinosaurs from smallest to biggest

    Why it works: Dinosaurs can be ordered by size, and the full spread runs from tiny to gigantic.

    1. Take a jumbled set of several dinosaurs (including a chicken-sized one and a long-necked giant) and arrange them in a line from shortest to longest (smallest to largest by length).
    2. Say which is smallest and which is largest, and name one of each if you can (e.g. Compsognathus small, Brachiosaurus large).
    3. Attach or say a comparative word for each neighbouring pair (this one is longer than that one).
  3. 3

    To-scale line-up poster (scaffold)

    Why it works: A fair comparison uses a common scale, and a single picture can show the full range at once.

    1. Look at a poster where dinosaurs are drawn beside a bus, a house, and a child at the same shared scale.
    2. Point to each dinosaur and read or say its comparison: 'as tall as a house', 'as small as a chicken'.
    3. Find the biggest and the smallest on the poster and describe the difference.

Science // Dinosaurs & Paleontology