Dinosaurs & Prehistoric Life · Unit 5
The Age of Dinosaurs
Triassic, Jurassic and Cretaceous, and how deep time works
The Mesozoic lasted roughly 180 million years, and dinosaurs are routinely presented as if they all lived at once. They did not, by an enormous margin.
The unit covers the Triassic, Jurassic and Cretaceous in turn, what changed between them, and the scale of deep time - which is the hardest single idea in the subject.
This unit breaks down into 18 short steps and 110 questions, starting at difficulty 1 and building to 3. Below you can see exactly what it covers, how the path is structured, and worked examples with explanations.
- Steps
- 18
- Questions
- 110
- Difficulty
- 1-3
What this unit covers
- The Triassic
- The Cretaceous
- The Jurassic
- The Mesozoic Era
- Millions of Years
Where this fits
Best early. It supplies the timeline every other unit refers to.
Where people slip
Stegosaurus and Tyrannosaurus never met, and the gap between them is larger than the gap between Tyrannosaurus and us.
How the unit is structured
The Age of Dinosaurs runs as 18 short steps that unlock in order. 13 are practice rounds and 5 are challenge rounds that pull together everything before them. Questions start at difficulty 1 and climb to 3 as you progress.
Challenge rounds
Example questions
30 real questions from this unit, with the answer and the reason behind it, grouped by what they practise. There are 110 in the unit altogether.
Millions of Years
- Multiple choiceLevel 1
1. About how old is the Earth?
- About 4.5 billion yearscorrect
- About 6000 years
- About 66 million years
- About 1 million years
Earth formed about 4.5 billion years ago.
- True or falseLevel 1
2. Humans have existed for a tiny fraction of Earth's history.
Answer: True
True. Our species is only about three hundred thousand years old.
- Build the sentenceLevel 2
3. Build a sentence about the age of dinosaurs.
Answer: Dinosaurs ruled for millions of years
Dinosaurs ruled the land for millions of years.
- Match the pairsLevel 2
4. Match each period to something that happened in it.
Answer: Triassic = The first dinosaurs appear; Jurassic = Giant sauropods dominate; Cretaceous = Flowering plants spread
Each period of the Mesozoic has its own landmark events.
- Put in orderLevel 2
5. Put these eras in order from oldest to youngest.
Answer: Palaeozoic -> Mesozoic -> Cenozoic
Palaeozoic, then Mesozoic, then Cenozoic.
- Fact or fibLevel 3
6. The geological time scale was built by comparing rock layers and fossils across many countries.
Answer: True
True. It took generations of careful correlation.
The Cretaceous
- Fill the blankLevel 1
7. By the Cretaceous, the continents were drifting towards their ____ positions.
- moderncorrect
- frozen
- underwater
- original
The map was slowly starting to look familiar.
- True or falseLevel 1
8. The Cretaceous was the last period of the age of dinosaurs.
Answer: True
True. It ended with the great extinction 66 million years ago.
- Choose all that applyLevel 2
9. Which dinosaurs lived in the Cretaceous? Pick all that apply.
- Velociraptorcorrect
- Triceratopscorrect
- Spinosauruscorrect
- Stegosaurus
Velociraptor, Triceratops and Spinosaurus are all Cretaceous.
- Fact or fibLevel 2
10. Bees and butterflies appeared alongside flowering plants in the Cretaceous.
Answer: True
True. Flowers and their pollinators rose together.
- Multiple choiceLevel 2
11. Which important kind of plant spread widely during the Cretaceous?
- Flowering plantscorrect
- Grass lawns
- Coffee bushes
- Wheat fields
Flowering plants appeared and spread across the world in the Cretaceous.
- Sort into groupsLevel 2
12. Sort each dinosaur into the period it lived in.
Answer: Coelophysis = Triassic; Allosaurus = Jurassic; Velociraptor = Cretaceous; Tyrannosaurus = Cretaceous
Knowing the period helps avoid mixing up dinosaurs that never met.
The Jurassic
- Choose all that applyLevel 1
13. Which dinosaurs lived in the Jurassic? Pick all that apply.
- Diplodocuscorrect
- Allosauruscorrect
- Stegosauruscorrect
- Triceratops
Diplodocus, Allosaurus and Stegosaurus are all Jurassic.
- Type the answerLevel 1
14. Which mountain range in Europe gave the Jurassic period its name?
Answer: Jura
The Jura Mountains gave the period its name.
- Fact or fibLevel 2
15. The earliest known bird-like dinosaur, Archaeopteryx, comes from the Jurassic.
Answer: True
True. It lived about 150 million years ago in what is now Germany.
- Multiple choiceLevel 2
16. Which period is famous for the biggest long-necked dinosaurs?
- The Jurassiccorrect
- The Triassic
- The Ice Age
- The Cambrian
The Jurassic was the great age of giant sauropods.
- True or falseLevel 2
17. Stegosaurus and Allosaurus both lived in the Jurassic.
Answer: True
True. They shared the same Late Jurassic landscapes.
- Match the pairsLevel 3
18. Match each dating method to what it measures.
Answer: Radiometric dating = Age in years from decay; Biostratigraphy = Order from fossil species; Magnetostratigraphy = Magnetic field reversals; Chemostratigraphy = Chemical signals in rock
Different methods answer different questions about time.
The Mesozoic Era
- Multiple choiceLevel 1
19. What is the Age of Dinosaurs also called?
- The Mesozoic Eracorrect
- The Ice Age
- The Stone Age
- The Space Age
The Mesozoic Era is the age of the dinosaurs.
- Put in orderLevel 1
20. Put the three periods of the Mesozoic in order.
Answer: Triassic -> Jurassic -> Cretaceous
Triassic, then Jurassic, then Cretaceous.
- True or falseLevel 1
21. The Mesozoic Era lasted far longer than humans have existed.
Answer: True
True. It ran for about 186 million years.
- Choose all that applyLevel 2
22. Which eras belong to the Phanerozoic eon? Pick all that apply.
- Palaeozoiccorrect
- Mesozoiccorrect
- Cenozoiccorrect
- Jurassic
Palaeozoic, Mesozoic and Cenozoic make up the eon of visible life.
- Fill the blankLevel 2
23. The three periods of the Mesozoic are the Triassic, the Jurassic and the ____.
- Cretaceouscorrect
- Cambrian
- Carboniferous
- Silurian
The Cretaceous is the last and longest of the three.
- Guess the numberLevel 2
24. How many periods are there in the Mesozoic Era?
Answer: 3 periods
Triassic, Jurassic and Cretaceous make three.
The Triassic
- Fact or fibLevel 1
25. Dinosaurs ruled the world from the very moment they first appeared.
Answer: False
False. For millions of years they shared the land with other big reptiles before becoming dominant.
- True or falseLevel 1
26. The first dinosaurs were small compared with the giants that came later.
Answer: True
True. Early dinosaurs were often only a couple of metres long.
- Choose all that applyLevel 2
27. Which appeared during the Triassic? Pick all that apply.
- The first dinosaurscorrect
- The first pterosaurscorrect
- The first mammalscorrect
- The first flowering plants
Dinosaurs, pterosaurs and mammals all first appear in the Triassic.
- Fill the blankLevel 2
28. The first dinosaurs appeared about ____ million years ago.
- 230correct
- 66
- 20
- 5
The earliest known dinosaurs date to roughly 230 million years ago.
- Multiple choiceLevel 2
29. What was the giant supercontinent of the Triassic called?
- Pangaeacorrect
- Atlantis
- Eurasia
- Antarctica
Pangaea joined nearly all the land into one mass.
- Type the answerLevel 2
30. What was the name of the supercontinent where the first dinosaurs lived?
Answer: Pangaea
Pangaea means all earth.
Where these questions come from. Each unit starts as a plan of the concepts it should cover and the difficulty it should span. Questions are written against that plan with AI assistance, then checked by a validator that rejects anything without a single defensible answer, an explanation, or plausible wrong options. How we write questions sets out the whole process, and corrections are fixed in the bank and reach the site and the app the same day.
How you practise
This unit mixes 11 different question formats, so you are recalling and applying rather than recognising the same layout every time.
- Build the sentence
- Choose all that apply
- Fact or fib
- Fill the blank
- Guess the number
- Match the pairs
- Multiple choice
- Put in order
- Sort into groups
- True or false
- Type the answer
Practise The Age of Dinosaurs
110 questions across 18 steps. Start with step one and crawl at your own pace.
Play this unitRead about The Age of Dinosaurs
Explainers from our blog on what this unit covers. Each one ends with real questions from the bank.
- What Are the Triassic, Jurassic and Cretaceous Periods?The three chapters of the age of dinosaurs, what lived in each, and how they ended.August 28, 2026 · 6 min read
- What Were the First Mammals? Two Hundred Million Years in the ShadowsMammals appeared alongside the first dinosaurs, not after them, and spent their first 150 million years small and mostly nocturnal.September 14, 2026 · 4 min read
- What Were Trilobites? The Animals That Ruled the Seas for 270 Million YearsTrilobites were armoured sea creatures with the first complex eyes, and they outlasted almost every other animal group. What they were and why they vanished.September 14, 2026 · 4 min read
More units in Dinosaurs & Prehistoric Life
- What Is a Dinosaur?What dinosaurs were, when they lived and how we name them
- Famous DinosaursTyrannosaurus, Triceratops, Stegosaurus and the other stars
- Meat Eaters and Plant EatersTeeth, claws, defences and what dinosaurs ate
- Fossils and Fossil HuntingWhat fossils are, how they form and how they are found
- Eggs, Nests and Growing UpDinosaur eggs, nests, babies and family life
- Flying and Swimming ReptilesPterosaurs, plesiosaurs and the sea monsters that were not dinosaurs
- The Great ExtinctionThe asteroid, the volcanoes and who survived
- Dinosaurs and BirdsFeathers, Archaeopteryx and the dinosaurs still alive today