The Big Bang theory

Explain the Big Bang theory as the expansion of space from a hot, dense state about 13.8 billion years ago and apply Hubble's law.

⏱ 18 min❓ 8 questions

What you'll be able to do

✔I can explain the Big Bang theory as the expansion of space from a hot, dense state
✔I can sequence key events in the history of the universe
✔I can use Hubble's law to relate a galaxy's distance to its recession speed

How this works

1Read the short explanations first — they teach you what you need before each question.
2Answer each question, then tap Check. A right answer moves you on automatically; if it's wrong, you'll see a friendly explanation of why.
3Finish all 3 steps to see your score — sign in and subscribe to unlock the full lesson and save it.

What's inside

8 questions and 1 quick teaching card, including:

🔢Number answer — Work out the answer and type the number.
↕️Put in order — Use the up and down arrows to sort the steps.

👪Grown-up tip: sit alongside younger learners for the first few lessons. Read the questions together and chat about the explanations — that's where the real learning sticks.

Curriculum: AC9S10U03